diff --git a/CHANGELOG b/CHANGELOG
index e30752dfd6..c61b73916a 100644
--- a/CHANGELOG
+++ b/CHANGELOG
@@ -1,12 +1,17 @@
 v2.1.0 (XXXX-XX-XX)
 -------------------
 
+* don't requeue identical context methods in V8 threads in case a method is 
+  already registered
+
 * removed arangod command line option `--database.remove-on-compacted`
 
 
 v2.0.1 (XXXX-XX-XX)
 -------------------
 
+* fixed display of missing error messages and codes in arangosh
+
 * when creating a collection via the web interface, the collection type was always 
   "document", regardless of the user's choice
 
diff --git a/UnitTests/Makefile.unittests b/UnitTests/Makefile.unittests
index c49a046cc5..b630ca6dce 100755
--- a/UnitTests/Makefile.unittests
+++ b/UnitTests/Makefile.unittests
@@ -363,6 +363,7 @@ SHELL_COMMON = \
                @top_srcdir@/js/common/tests/shell-document.js \
                @top_srcdir@/js/common/tests/shell-download.js \
                @top_srcdir@/js/common/tests/shell-edge.js \
+               @top_srcdir@/js/common/tests/shell-errors.js \
                @top_srcdir@/js/common/tests/shell-fs.js \
                @top_srcdir@/js/common/tests/shell-graph-traversal.js \
                @top_srcdir@/js/common/tests/shell-graph-algorithms.js \
diff --git a/arangod/V8Server/ApplicationV8.cpp b/arangod/V8Server/ApplicationV8.cpp
index cef629a599..2d94bb0964 100644
--- a/arangod/V8Server/ApplicationV8.cpp
+++ b/arangod/V8Server/ApplicationV8.cpp
@@ -60,6 +60,32 @@ using namespace triagens::arango;
 using namespace triagens::rest;
 using namespace std;
 
+// -----------------------------------------------------------------------------
+// --SECTION--                                        class GlobalContextMethods
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief initialise code for pre-defined actions
+////////////////////////////////////////////////////////////////////////////////
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief reload the routing cache
+////////////////////////////////////////////////////////////////////////////////
+
+std::string const GlobalContextMethods::CodeReloadRouting    = "require(\"org/arangodb/actions\").reloadRouting()";
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief flush the modules cache
+////////////////////////////////////////////////////////////////////////////////
+
+std::string const GlobalContextMethods::CodeFlushModuleCache = "require(\"internal\").flushModuleCache()";
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief reload AQL functions
+////////////////////////////////////////////////////////////////////////////////
+
+std::string const GlobalContextMethods::CodeReloadAql        = "try { require(\"org/arangodb/ahuacatl\").reload(); } catch (err) { }";
+
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief we'll store deprecated config option values in here
 ////////////////////////////////////////////////////////////////////////////////
@@ -128,10 +154,25 @@ namespace {
 /// @brief adds a global method
 ////////////////////////////////////////////////////////////////////////////////
 
-void ApplicationV8::V8Context::addGlobalContextMethod (string const& method) {
-  MUTEX_LOCKER(_globalMethodsLock);
+bool ApplicationV8::V8Context::addGlobalContextMethod (string const& method) {
+  GlobalContextMethods::MethodType type = GlobalContextMethods::getType(method);
 
-  _globalMethods.push_back(method);
+  if (type == GlobalContextMethods::TYPE_UNKNOWN) {
+    return false;
+  }
+
+  MUTEX_LOCKER(_globalMethodsLock);
+  
+  for (size_t i = 0; i < _globalMethods.size(); ++i) {
+    if (_globalMethods[i] == type) {
+      // action is already registered. no need to register it again
+      return true;
+    }
+  }
+
+  // insert action into vector
+  _globalMethods.push_back(type);
+  return true;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
@@ -141,7 +182,7 @@ void ApplicationV8::V8Context::addGlobalContextMethod (string const& method) {
 void ApplicationV8::V8Context::handleGlobalContextMethods () {
   v8::HandleScope scope;
 
-  vector<string> copy;
+  vector<GlobalContextMethods::MethodType> copy;
 
   {
     // we need to copy the vector of functions so we do not need to hold the
@@ -153,13 +194,14 @@ void ApplicationV8::V8Context::handleGlobalContextMethods () {
     _globalMethods.clear();
   }
 
-  for (vector<string>::const_iterator i = copy.begin();  i != copy.end();  ++i) {
-    string const& func = *i;
+  for (vector<GlobalContextMethods::MethodType>::const_iterator i = copy.begin();  i != copy.end();  ++i) {
+    GlobalContextMethods::MethodType const type = *i;
+    string const func = GlobalContextMethods::getCode(type);
 
     LOG_DEBUG("executing global context methods '%s' for context %d", func.c_str(), (int) _id);
 
     TRI_ExecuteJavaScriptString(_context,
-                                v8::String::New(func.c_str()),
+                                v8::String::New(func.c_str(), func.size()),
                                 v8::String::New("global context method"),
                                 false);
   }
@@ -366,10 +408,16 @@ void ApplicationV8::exitContext (V8Context* context) {
 /// @brief adds a global context functions to be executed asap
 ////////////////////////////////////////////////////////////////////////////////
 
-void ApplicationV8::addGlobalContextMethod (string const& method) {
+bool ApplicationV8::addGlobalContextMethod (string const& method) {
+  bool result = true;
+
   for (size_t i = 0; i < _nrInstances; ++i) {
-    _contexts[i]->addGlobalContextMethod(method);
+    if (! _contexts[i]->addGlobalContextMethod(method)) {
+      result = false;
+    }
   }
+
+  return result;
 }
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/arangod/V8Server/ApplicationV8.h b/arangod/V8Server/ApplicationV8.h
index 36db91b951..2d2e4aa745 100644
--- a/arangod/V8Server/ApplicationV8.h
+++ b/arangod/V8Server/ApplicationV8.h
@@ -55,12 +55,76 @@ namespace triagens {
     class ApplicationScheduler;
   }
 
+  namespace arango {
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                        class GlobalContextMethods
+// -----------------------------------------------------------------------------
+
+    class GlobalContextMethods {
+  
+      public:
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief method type
+////////////////////////////////////////////////////////////////////////////////
+
+        enum MethodType {
+          TYPE_UNKNOWN = 0,
+          TYPE_RELOAD_ROUTING,
+          TYPE_FLUSH_MODULE_CACHE,
+          TYPE_RELOAD_AQL
+        };
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief get a method type number from a type string
+////////////////////////////////////////////////////////////////////////////////
+
+        static MethodType getType (std::string const& type) {
+          if (type == "reloadRouting") {
+            return TYPE_RELOAD_ROUTING;
+          }
+          if (type == "flushModuleCache") {
+            return TYPE_FLUSH_MODULE_CACHE;
+          }
+          if (type == "reloadAql") {
+            return TYPE_RELOAD_AQL;
+          }
+
+          return TYPE_UNKNOWN;
+        }
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief get code for a method
+////////////////////////////////////////////////////////////////////////////////
+
+        static std::string const getCode (MethodType type) {
+          switch (type) {
+            case TYPE_RELOAD_ROUTING:
+              return CodeReloadRouting;
+            case TYPE_FLUSH_MODULE_CACHE:
+              return CodeFlushModuleCache;
+            case TYPE_RELOAD_AQL:
+              return CodeReloadAql;
+            case TYPE_UNKNOWN:
+            default:
+              return "";
+          }
+        }
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief static strings with the code for each method
+////////////////////////////////////////////////////////////////////////////////
+
+        static std::string const CodeReloadRouting;
+        static std::string const CodeFlushModuleCache;
+        static std::string const CodeReloadAql;
+    };
+
 // -----------------------------------------------------------------------------
 // --SECTION--                                               class ApplicationV8
 // -----------------------------------------------------------------------------
 
-  namespace arango {
-
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief application simple user and session management feature
 ////////////////////////////////////////////////////////////////////////////////
@@ -112,7 +176,7 @@ namespace triagens {
 /// Caller must hold the _contextCondition.
 ////////////////////////////////////////////////////////////////////////////////
 
-          void addGlobalContextMethod (string const&);
+          bool addGlobalContextMethod (string const&);
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief executes all global methods
@@ -132,7 +196,7 @@ namespace triagens {
 /// @brief open global methods
 ////////////////////////////////////////////////////////////////////////////////
 
-          std::vector<std::string> _globalMethods;
+          std::vector<GlobalContextMethods::MethodType> _globalMethods;
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief number of requests since last GC of the context
@@ -230,7 +294,7 @@ namespace triagens {
 /// @brief adds a global context functions to be executed asap
 ////////////////////////////////////////////////////////////////////////////////
 
-        void addGlobalContextMethod (string const&);
+        bool addGlobalContextMethod (string const&);
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief runs the garbage collection
diff --git a/arangod/V8Server/v8-actions.cpp b/arangod/V8Server/v8-actions.cpp
index 06034ccc1c..54273efcb3 100644
--- a/arangod/V8Server/v8-actions.cpp
+++ b/arangod/V8Server/v8-actions.cpp
@@ -784,7 +784,7 @@ static v8::Handle<v8::Value> JS_ExecuteGlobalContextFunction (v8::Arguments cons
   v8::HandleScope scope;
 
   if (argv.Length() != 1) {
-    TRI_V8_EXCEPTION_USAGE(scope, "executeGlobalContextFunction(<function-definition>)");
+    TRI_V8_EXCEPTION_USAGE(scope, "executeGlobalContextFunction(<function-type>)");
   }
 
   // extract the action name
@@ -794,10 +794,12 @@ static v8::Handle<v8::Value> JS_ExecuteGlobalContextFunction (v8::Arguments cons
     TRI_V8_TYPE_ERROR(scope, "<definition> must be a UTF-8 function definition");
   }
 
-  string def = *utf8def;
+  string const def = *utf8def;
 
   // and pass it to the V8 contexts
-  GlobalV8Dealer->addGlobalContextMethod(def);
+  if (! GlobalV8Dealer->addGlobalContextMethod(def)) {
+    TRI_V8_EXCEPTION_MESSAGE(scope, TRI_ERROR_INTERNAL, "invalid action definition");
+  }
 
   return scope.Close(v8::Undefined());
 }
diff --git a/arangod/V8Server/v8-query.cpp b/arangod/V8Server/v8-query.cpp
index e919e973b6..c13f25a77a 100644
--- a/arangod/V8Server/v8-query.cpp
+++ b/arangod/V8Server/v8-query.cpp
@@ -2013,7 +2013,7 @@ static v8::Handle<v8::Value> JS_ByExampleQuery (v8::Arguments const& argv) {
   size_t total = filtered._length;
   size_t count = 0;
   bool error = false;
-
+  
   if (0 < total) {
     size_t s;
     size_t e;
diff --git a/arangod/V8Server/v8-vocbase.cpp b/arangod/V8Server/v8-vocbase.cpp
index 97ff824a72..16fa1a568a 100644
--- a/arangod/V8Server/v8-vocbase.cpp
+++ b/arangod/V8Server/v8-vocbase.cpp
@@ -6076,6 +6076,7 @@ static v8::Handle<v8::Value> JS_DatafileScanVocbaseCol (v8::Arguments const& arg
   result->Set(v8::String::New("endPosition"), v8::Number::New(scan._endPosition));
   result->Set(v8::String::New("numberMarkers"), v8::Number::New(scan._numberMarkers));
   result->Set(v8::String::New("status"), v8::Number::New(scan._status));
+  result->Set(v8::String::New("isSealed"), v8::Boolean::New(scan._isSealed));
 
   v8::Handle<v8::Array> entries = v8::Array::New();
   result->Set(v8::String::New("entries"), entries);
@@ -10460,7 +10461,7 @@ void TRI_V8ReloadRouting (v8::Handle<v8::Context> context) {
   v8::HandleScope scope;      
 
   TRI_ExecuteJavaScriptString(context,
-                              v8::String::New("require('internal').executeGlobalContextFunction('require(\\'org/arangodb/actions\\').reloadRouting()')"),
+                              v8::String::New("require('internal').executeGlobalContextFunction('reloadRouting')"),
                               v8::String::New("reload routing"),
                               false);
 }
diff --git a/arangod/VocBase/datafile.c b/arangod/VocBase/datafile.c
index 98d55db53e..7f4ffabd42 100644
--- a/arangod/VocBase/datafile.c
+++ b/arangod/VocBase/datafile.c
@@ -31,6 +31,7 @@
 
 #include "datafile.h"
 
+#include "BasicsC/conversions.h"
 #include "BasicsC/hashes.h"
 #include "BasicsC/logging.h"
 #include "BasicsC/memory-map.h"
@@ -421,6 +422,7 @@ static TRI_df_scan_t ScanDatafile (TRI_datafile_t const* datafile) {
   scan._maximalSize = datafile->_maximalSize;
   scan._numberMarkers = 0;
   scan._status = 1;
+  scan._isSealed = false; // assume false
 
   if (datafile->_currentSize == 0) {
     end = datafile->_data + datafile->_maximalSize;
@@ -494,6 +496,7 @@ static TRI_df_scan_t ScanDatafile (TRI_datafile_t const* datafile) {
 
     if (marker->_type == TRI_DF_MARKER_FOOTER) {
       scan._endPosition = currentSize;
+      scan._isSealed = true;
       return scan;
     }
 
@@ -1712,6 +1715,7 @@ TRI_df_scan_t TRI_ScanDatafile (char const* path) {
     TRI_InitVector(&scan._entries, TRI_CORE_MEM_ZONE, sizeof(TRI_df_scan_entry_t));
 
     scan._status = 5;
+    scan._isSealed = false;
   }
 
   return scan;
diff --git a/arangod/VocBase/datafile.h b/arangod/VocBase/datafile.h
index 97ddd661c6..142330b1de 100644
--- a/arangod/VocBase/datafile.h
+++ b/arangod/VocBase/datafile.h
@@ -214,6 +214,7 @@ typedef struct TRI_df_scan_s {
   TRI_vector_t   _entries;
 
   uint32_t _status;
+  bool _isSealed;
 }
 TRI_df_scan_t;
 
diff --git a/arangod/VocBase/server.c b/arangod/VocBase/server.c
index 806b602b54..ba4273c729 100644
--- a/arangod/VocBase/server.c
+++ b/arangod/VocBase/server.c
@@ -803,7 +803,7 @@ static int OpenDatabases (TRI_server_t* server,
                               databaseName, 
                               &defaults,
                               isUpgrade, 
-                              server->_wasShutdownCleanly);
+                              ! server->_wasShutdownCleanly);
 
     TRI_FreeString(TRI_CORE_MEM_ZONE, databaseName);
 
@@ -1863,6 +1863,7 @@ int TRI_StartServer (TRI_server_t* server,
     return TRI_ERROR_INTERNAL;
   }
 
+
   server->_wasShutdownCleanly = (res == TRI_ERROR_NO_ERROR);
 
 
diff --git a/arangod/VocBase/vocbase.c b/arangod/VocBase/vocbase.c
index 6336850c01..0eddf818d4 100644
--- a/arangod/VocBase/vocbase.c
+++ b/arangod/VocBase/vocbase.c
@@ -1104,7 +1104,7 @@ static int LoadCollectionVocBase (TRI_vocbase_t* vocbase,
     // release the lock on the collection temporarily
     // this will allow other threads to check the collection's
     // status while it is loading (loading may take a long time because of
-    // disk activity)
+    // disk activity, index creation etc.)
     TRI_WRITE_UNLOCK_STATUS_VOCBASE_COL(collection);
 
     document = TRI_OpenDocumentCollection(vocbase, collection->_path);
diff --git a/etc/arangodb/arango-dfdb.conf.in b/etc/arangodb/arango-dfdb.conf.in
index 8c3397eb43..71ac8eeb49 100644
--- a/etc/arangodb/arango-dfdb.conf.in
+++ b/etc/arangodb/arango-dfdb.conf.in
@@ -5,6 +5,10 @@ directory= @LOCALSTATEDIR@/lib/arangodb
 # maximal-journal-size=33554432
 # remove-on-drop=true
 
+[server]
+# set number of threads to 1 so we don't have concurrency
+threads = 1
+
 [javascript]
 startup-directory = @PKGDATADIR@/js
 app-path = @LOCALSTATEDIR@/lib/arangodb-apps
diff --git a/etc/relative/arango-dfdb.conf b/etc/relative/arango-dfdb.conf
index 40be62e7c4..c4472606f0 100644
--- a/etc/relative/arango-dfdb.conf
+++ b/etc/relative/arango-dfdb.conf
@@ -7,6 +7,8 @@ no-upgrade = true
 
 [server]
 disable-authentication = true
+# set number of threads to 1 so we don't have concurrency
+threads = 1
 
 [javascript]
 startup-directory = ./js
diff --git a/js/actions/api-system.js b/js/actions/api-system.js
index 9e276c304c..70c4c87b01 100644
--- a/js/actions/api-system.js
+++ b/js/actions/api-system.js
@@ -219,7 +219,7 @@ actions.defineHttp({
   prefix : false,
 
   callback : function (req, res) {
-    internal.executeGlobalContextFunction("require(\"org/arangodb/actions\").reloadRouting()");
+    internal.executeGlobalContextFunction("reloadRouting");
     console.warn("about to flush the routing cache");
     actions.resultOk(req, res, actions.HTTP_OK);
   }
@@ -263,7 +263,7 @@ actions.defineHttp({
   prefix : false,
 
   callback : function (req, res) {
-    internal.executeGlobalContextFunction("require(\"internal\").flushModuleCache()");
+    internal.executeGlobalContextFunction("flushModuleCache");
     console.warn("about to flush the modules cache");
     actions.resultOk(req, res, actions.HTTP_OK);
   }
diff --git a/js/apps/system/aardvark/frontend/js/bootstrap/module-internal.js b/js/apps/system/aardvark/frontend/js/bootstrap/module-internal.js
index d0fe897c64..b9cc5ce840 100644
--- a/js/apps/system/aardvark/frontend/js/bootstrap/module-internal.js
+++ b/js/apps/system/aardvark/frontend/js/bootstrap/module-internal.js
@@ -82,20 +82,19 @@
       this.message = this.toString();
     };
   
-    exports.ArangoError.prototype = new Error(); //Error.prototype;
-    
-    exports.ArangoError.prototype._PRINT = function (context) {
-      context.output += this.toString();
-    };
+    exports.ArangoError.prototype = new Error(); 
+  } 
+  
+  exports.ArangoError.prototype._PRINT = function (context) {
+    context.output += this.toString();
+  };
 
-    exports.ArangoError.prototype.toString = function() {
-      var errorNum = this.errorNum;
-      var errorMessage = this.errorMessage || this.message;
+  exports.ArangoError.prototype.toString = function() {
+    var errorNum = this.errorNum;
+    var errorMessage = this.errorMessage || this.message;
 
-      return "[ArangoError " + errorNum + ": " + errorMessage + "]";
-    };
-
-  }
+    return "[ArangoError " + errorNum + ": " + errorMessage + "]";
+  };
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief SleepAndRequeue
diff --git a/js/common/bootstrap/module-internal.js b/js/common/bootstrap/module-internal.js
index d0fe897c64..b9cc5ce840 100644
--- a/js/common/bootstrap/module-internal.js
+++ b/js/common/bootstrap/module-internal.js
@@ -82,20 +82,19 @@
       this.message = this.toString();
     };
   
-    exports.ArangoError.prototype = new Error(); //Error.prototype;
-    
-    exports.ArangoError.prototype._PRINT = function (context) {
-      context.output += this.toString();
-    };
+    exports.ArangoError.prototype = new Error(); 
+  } 
+  
+  exports.ArangoError.prototype._PRINT = function (context) {
+    context.output += this.toString();
+  };
 
-    exports.ArangoError.prototype.toString = function() {
-      var errorNum = this.errorNum;
-      var errorMessage = this.errorMessage || this.message;
+  exports.ArangoError.prototype.toString = function() {
+    var errorNum = this.errorNum;
+    var errorMessage = this.errorMessage || this.message;
 
-      return "[ArangoError " + errorNum + ": " + errorMessage + "]";
-    };
-
-  }
+    return "[ArangoError " + errorNum + ": " + errorMessage + "]";
+  };
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief SleepAndRequeue
diff --git a/js/common/tests/shell-errors.js b/js/common/tests/shell-errors.js
new file mode 100644
index 0000000000..dba5a31620
--- /dev/null
+++ b/js/common/tests/shell-errors.js
@@ -0,0 +1,196 @@
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test the error codes
+///
+/// @file
+///
+/// DISCLAIMER
+///
+/// Copyright 2010-2012 triagens GmbH, Cologne, Germany
+///
+/// Licensed under the Apache License, Version 2.0 (the "License");
+/// you may not use this file except in compliance with the License.
+/// You may obtain a copy of the License at
+///
+///     http://www.apache.org/licenses/LICENSE-2.0
+///
+/// Unless required by applicable law or agreed to in writing, software
+/// distributed under the License is distributed on an "AS IS" BASIS,
+/// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+/// See the License for the specific language governing permissions and
+/// limitations under the License.
+///
+/// Copyright holder is triAGENS GmbH, Cologne, Germany
+///
+/// @author Jan Steemann
+/// @author Copyright 2012, triAGENS GmbH, Cologne, Germany
+////////////////////////////////////////////////////////////////////////////////
+
+var jsunity = require("jsunity");
+var arangodb = require("org/arangodb");
+var ArangoError = require("org/arangodb").ArangoError;
+var ERRORS = arangodb.errors;
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                            errors
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test suite
+////////////////////////////////////////////////////////////////////////////////
+
+function ErrorsSuite () {
+
+  var throwError = function (code, message) {
+    var err = new ArangoError();
+    err.errorNum = code; 
+    err.errorMessage = message;
+    throw err;
+  };
+
+  return {
+
+    setUp : function () {
+    },
+    
+    tearDown : function () {
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test built-in error
+////////////////////////////////////////////////////////////////////////////////
+
+    testBuiltIn : function () {
+      try {
+        throw "foo";
+        fail();
+      }
+      catch (err) {
+        assertFalse(err instanceof ArangoError);
+        assertEqual("string", typeof err);
+        assertEqual("foo", err);
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test built-in error
+////////////////////////////////////////////////////////////////////////////////
+
+    testTypeErrorBuiltIn : function () {
+      try {
+        throw new TypeError("invalid type!");
+        fail();
+      }
+      catch (err) {
+        assertFalse(err instanceof ArangoError);
+        assertEqual("invalid type!", err.message);
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test struct
+////////////////////////////////////////////////////////////////////////////////
+
+    testArangoErrorStruct : function () {
+      try {
+        throwError(1, "the foxx");
+        fail();
+      }
+      catch (err) {
+        assertTrue(err.hasOwnProperty("errorNum"));
+        assertTrue(err.hasOwnProperty("errorMessage"));
+        assertTrue(err.hasOwnProperty("error"));
+        
+        assertEqual("number", typeof err.errorNum);
+        assertEqual("string", typeof err.errorMessage);
+        assertEqual("boolean", typeof err.error);
+
+        assertEqual(1, err.errorNum);
+        assertEqual("the foxx", err.errorMessage);
+        assertTrue(err.error);
+
+        assertTrue(err instanceof ArangoError);
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test a custom code
+////////////////////////////////////////////////////////////////////////////////
+
+    testArangoErrorCustom : function () {
+      try {
+        throwError(12345, "myerrormessage");
+        fail();
+      }
+      catch (err) {
+        assertEqual(12345, err.errorNum);
+        assertEqual("myerrormessage", err.errorMessage);
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test a custom message
+////////////////////////////////////////////////////////////////////////////////
+
+    testArangoErrorMessage : function () {
+      try {
+        throwError(ERRORS.ERROR_ARANGO_DOCUMENT_TYPE_INVALID.code, ERRORS.ERROR_ARANGO_DOCUMENT_TYPE_INVALID.message);
+        fail();
+      }
+      catch (err) {
+        assertEqual(ERRORS.ERROR_ARANGO_DOCUMENT_TYPE_INVALID.code, err.errorNum);
+        assertEqual(ERRORS.ERROR_ARANGO_DOCUMENT_TYPE_INVALID.message, err.errorMessage);
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test to string
+////////////////////////////////////////////////////////////////////////////////
+
+    testArangoToString1 : function () {
+      var e = ERRORS.ERROR_ARANGO_DOCUMENT_TYPE_INVALID;
+      
+      try {
+        throwError(e.code, e.message);
+        fail();
+      }
+      catch (err) {
+        assertEqual("[ArangoError " + e.code + ": " + e.message + "]", err.toString());
+      }
+    },
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief test to string
+////////////////////////////////////////////////////////////////////////////////
+
+    testArangoToString2 : function () {
+      var e = ERRORS.ERROR_ARANGO_DOCUMENT_NOT_FOUND;
+      
+      try {
+        throwError(e.code, e.message + ": did not find document");
+        fail();
+      }
+      catch (err) {
+        assertEqual("[ArangoError " + e.code + ": " + e.message + ": did not find document]", err.toString());
+      }
+    }
+
+  };
+}
+
+// -----------------------------------------------------------------------------
+// --SECTION--                                                              main
+// -----------------------------------------------------------------------------
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief executes the test suite
+////////////////////////////////////////////////////////////////////////////////
+
+jsunity.run(ErrorsSuite);
+
+return jsunity.done();
+
+// Local Variables:
+// mode: outline-minor
+// outline-regexp: "^\\(/// @brief\\|/// @addtogroup\\|// --SECTION--\\|/// @page\\|/// @}\\)"
+// End:
+
diff --git a/js/server/arango-dfdb.js b/js/server/arango-dfdb.js
index 357aff0716..888f16744e 100644
--- a/js/server/arango-dfdb.js
+++ b/js/server/arango-dfdb.js
@@ -61,34 +61,52 @@ function WipeDatafile (collection, type, datafile, lastGoodPos) {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief checks a journal
+/// @brief queries user to wipe a datafile
 ////////////////////////////////////////////////////////////////////////////////
 
-function DeepCheckJournal (collection, type, datafile, scan, lastGoodPos) {
+function QueryWipeDatafile (collection, type, datafile, scan, lastGoodPos) {
   var entries = scan.entries;
 
   if (entries.length == 0) {
-    printf("WARNING: The journal is empty. Even the header is missing. Going\n");
-    printf("         to remove the datafile.\n");
+    if (type === "journal" || type === "compactor") {
+      printf("WARNING: The journal is empty. Even the header is missing. Going\n");
+      printf("         to remove the file.\n");
+    }
+    else {
+      printf("WARNING: The datafile is empty. Even the header is missing. Going\n");
+      printf("         to remove the datafile. This should never happen. Datafiles\n");
+      printf("         are append-only. Make sure your hard disk does not contain\n");
+      printf("         any hardware errors.\n");
+    }
     printf("\n");
 
     RemoveDatafile(collection, type, datafile);
-
     return;
   }
 
-  if (entries.length === lastGoodPos + 3 && entries[lastGoodPos + 2].status === 2) {
-    printf("WARNING: The journal was not closed properly, the last entry is corrupted.\n");
-    printf("         This might happen ArangoDB was killed and the last entry was not\n");
-    printf("         fully written to disk. Going to remove the last entry.\n");
-    printf("\n");
+  var ask = true;
+  if (type === "journal") {
+    if (entries.length === lastGoodPos + 3 && entries[lastGoodPos + 2].status === 2) {
+      printf("WARNING: The journal was not closed properly, the last entry is corrupted.\n");
+      printf("         This might happen ArangoDB was killed and the last entry was not\n");
+      printf("         fully written to disk. Going to remove the last entry.\n");
+      ask = false;
+    }
+    else {
+      printf("WARNING: The journal was not closed properly, the last entries are corrupted.\n");
+      printf("         This might happen ArangoDB was killed and the last entries were not\n");
+      printf("         fully written to disk.\n");
+    }
   }
   else {
-    printf("WARNING: The journal was not closed properly, the last entries is corrupted.\n");
-    printf("         This might happen ArangoDB was killed and the last entries were not\n");
-    printf("         fully written to disk.\n");
-    printf("\n");
+    printf("WARNING: The datafile contains corrupt entries. This should never happen.\n");
+    printf("         Datafiles are append-only. Make sure your hard disk does not contain\n");
+    printf("         any hardware errors.\n");
+  }
 
+  printf("\n");
+
+  if (ask) {
     printf("Wipe the last entries (Y/N)? ");
     var line = console.getline();
 
@@ -104,57 +122,34 @@ function DeepCheckJournal (collection, type, datafile, scan, lastGoodPos) {
 }
 
 ////////////////////////////////////////////////////////////////////////////////
-/// @brief checks a datafile
+/// @brief prints details about entries
 ////////////////////////////////////////////////////////////////////////////////
 
-function DeepCheckDatafile (collection, type, datafile, scan, lastGoodPos) {
-  var entries = scan.entries;
+function PrintEntries (entries, amount) {
+  var start, end;
 
-  if (entries.length == 0) {
-    printf("WARNING: The datafile is empty. Even the header is missing. Going\n");
-    printf("         to remove the datafile. This should never happen. Datafiles\n");
-    printf("         are append-only. Make sure your hard disk does not contain\n");
-    printf("         any hardware errors.\n");
-    printf("\n");
+  if (amount > 0) {
+    start = 0;
+    end = amount; 
+    if (end > entries.length) {
+      end = entries.length;
+    }
+  }
+  else {
+    start = entries.length + amount - 1;
+    if (start < 0) {
+      return;
+    }
+    if (start < Math.abs(amount)) {
+      return;
+    }
 
-    RemoveDatafile(collection, type, datafile);
-
-    return;
+    end = entries.length;
   }
 
-  printf("WARNING: The datafile contains corrupt entries. This should never happen.\n");
-  printf("         Datafiles are append-only. Make sure your hard disk does not contain\n");
-  printf("         any hardware errors.\n");
-  printf("\n");
-
-  printf("Wipe the last entries (Y/N)? ");
-  var line = console.getline();
-
-  if (line !== "yes" && line !== "YES" && line !== "y" && line !== "Y") {
-    printf("ABORTING\n");
-    return;
-  }
-
-  var entry = entries[lastGoodPos];
-
-  WipeDatafile(collection, type, datafile, entry.position + entry.size);
-}
-
-////////////////////////////////////////////////////////////////////////////////
-/// @brief checks a datafile deeply
-////////////////////////////////////////////////////////////////////////////////
-
-function DeepCheckDatafile (collection, type, datafile, scan) {
-  var entries = scan.entries;
-
-  printf("Entries\n");
-
-  var lastGood = 0;
-  var lastGoodPos = 0;
-  var stillGood = true;
-
-  for (var i = 0;  i < entries.length;  ++i) {
+  for (var i = start;  i < end;  ++i) {
     var entry = entries[i];
+
     var s = "unknown";
 
     switch (entry.status) {
@@ -165,7 +160,31 @@ function DeepCheckDatafile (collection, type, datafile, scan) {
       case 5: s = "FAILED (crc mismatch)";  break;
     }
 
-    printf("  %d: status %s type %d size %d\n", i, s, entry.type, entry.size);
+    printf("  %d: status %s type %d size %d, tick %s\n", i, s, entry.type, entry.size, entry.tick);
+  }
+}
+
+////////////////////////////////////////////////////////////////////////////////
+/// @brief checks a datafile deeply
+////////////////////////////////////////////////////////////////////////////////
+
+function DeepCheckDatafile (collection, type, datafile, scan, details) {
+  var entries = scan.entries;
+
+  printf("Entries\n");
+
+  var lastGood = 0;
+  var lastGoodPos = 0;
+  var stillGood = true;
+
+  if (details) {
+    // print details
+    PrintEntries(entries, 10);
+    PrintEntries(entries, -10);
+  }
+
+  for (var i = 0;  i < entries.length;  ++i) {
+    var entry = entries[i];
 
     if (entry.status === 1 || entry.status === 2) {
       if (stillGood) {
@@ -182,12 +201,7 @@ function DeepCheckDatafile (collection, type, datafile, scan) {
     printf("  Last good position: %d\n", lastGood.position + lastGood.size);
     printf("\n");
 
-    if (type === "journal" || type === "compactor") {
-      DeepCheckJournal(collection, type, datafile, scan, lastGoodPos);
-    }
-    else {
-      DeepCheckDatafile(collection, type, datafile, scan, lastGoodPos);
-    }
+    QueryWipeDatafile(collection, type, datafile, scan, lastGoodPos);
   }
 
   printf("\n");
@@ -197,7 +211,7 @@ function DeepCheckDatafile (collection, type, datafile, scan) {
 /// @brief checks a datafile
 ////////////////////////////////////////////////////////////////////////////////
 
-function CheckDatafile (collection, type, datafile, issues) {
+function CheckDatafile (collection, type, datafile, issues, details) {
   printf("Datafile\n");
   printf("  path: %s\n", datafile);
   printf("  type: %s\n", type);
@@ -208,6 +222,8 @@ function CheckDatafile (collection, type, datafile, issues) {
   printf("  maximal size: %d\n", scan.maximalSize);
   printf("  total used: %d\n", scan.endPosition);
   printf("  # of entries: %d\n", scan.numberMarkers);
+  printf("  status: %d\n", scan.status);
+  printf("  isSealed: %s\n", scan.isSealed ? "yes" : "no");
 
   // set default value to unknown
   var statusMessage = "UNKNOWN (" + scan.status + ")"; 
@@ -217,9 +233,12 @@ function CheckDatafile (collection, type, datafile, issues) {
     case 1:
       statusMessage = "OK";
       color = internal.COLORS.COLOR_GREEN;
+      if (! scan.isSealed && type === "datafile") {
+        color = internal.COLORS.COLOR_YELLOW;
+      }
       break;
 
-    case 1:
+    case 2:
       statusMessage = "NOT OK (reached empty marker)";
       color = internal.COLORS.COLOR_RED;
       break;
@@ -296,7 +315,7 @@ function CheckDatafile (collection, type, datafile, issues) {
     return;
   }
 
-  if (scan.entries.length == 2 && scan.entries[1].type !== 2000) {
+  if (scan.entries.length === 2 && scan.entries[1].type !== 2000) {
     // asserting a TRI_COL_MARKER_HEADER as second marker
     statusMessage = "datafile contains no collection header marker at pos #1!";
     color = internal.COLORS.COLOR_YELLOW;
@@ -316,19 +335,40 @@ function CheckDatafile (collection, type, datafile, issues) {
     RemoveDatafile(collection, type, datafile);
     return;
   }
+  
+  if (type !== "journal" && scan.entries.length === 3 && scan.entries[2].type === 0) {
+    // got the two initial header markers but nothing else...
+    statusMessage = "datafile is empty but not sealed";
+    color = internal.COLORS.COLOR_YELLOW;
 
-  if (scan.status === 1) {
+    issues.push({
+      collection: collection.name(), 
+      path: datafile, 
+      type: type, 
+      status: scan.status, 
+      message: statusMessage,
+      color: color
+    });
+
+    printf(color);
+    printf("WARNING: %s\n", statusMessage);
+    printf(internal.COLORS.COLOR_RESET);
+    RemoveDatafile(collection, type, datafile);
     return;
   }
 
-  DeepCheckDatafile(collection, type, datafile, scan);
+  if (scan.status === 1 && scan.isSealed) {
+    return;
+  }
+
+  DeepCheckDatafile(collection, type, datafile, scan, details);
 }
 
 ////////////////////////////////////////////////////////////////////////////////
 /// @brief checks a collection
 ////////////////////////////////////////////////////////////////////////////////
 
-function CheckCollection (collection, issues) {
+function CheckCollection (collection, issues, details) {
   printf("Database\n");
   printf("  name: %s\n", internal.db._name());
   printf("  path: %s\n", internal.db._path());
@@ -348,15 +388,15 @@ function CheckCollection (collection, issues) {
   printf("\n");
 
   for (var i = 0;  i < datafiles.journals.length;  ++i) {
-    CheckDatafile(collection, "journal", datafiles.journals[i], issues);
+    CheckDatafile(collection, "journal", datafiles.journals[i], issues, details);
   }
 
   for (var i = 0;  i < datafiles.datafiles.length;  ++i) {
-    CheckDatafile(collection, "datafiles", datafiles.datafiles[i], issues);
+    CheckDatafile(collection, "datafile", datafiles.datafiles[i], issues, details);
   }
 
   for (var i = 0;  i < datafiles.compactors.length;  ++i) {
-    CheckDatafile(collection, "compactor", datafiles.compactors[i], issues);
+    CheckDatafile(collection, "compactor", datafiles.compactors[i], issues, details);
   }
 }
 
@@ -378,7 +418,7 @@ function main (argv) {
 
     return 0;
   };
-
+  
   printf("%s\n", "    ___      _         __ _ _           ___  ___    ___ ");
   printf("%s\n", "   /   \\__ _| |_ __ _ / _(_) | ___     /   \\/ __\\  / _ \\");
   printf("%s\n", "  / /\\ / _` | __/ _` | |_| | |/ _ \\   / /\\ /__\\// / /_\\/");
@@ -398,9 +438,11 @@ function main (argv) {
     printf("  %d: %s\n", i, databases[i]);
   }
   
+  var line;
+  
   printf("Database to check: ");
   while (true) {
-    var line = console.getline();
+    line = console.getline();
    
     if (line == "") {
       printf("Exiting. Please wait.\n");
@@ -445,7 +487,7 @@ function main (argv) {
   var a = [];
   
   while (true) {
-    var line = console.getline();
+    line = console.getline();
 
     if (line == "") {
       printf("Exiting. Please wait.\n");
@@ -471,6 +513,23 @@ function main (argv) {
       }
     }
   }
+  
+  printf("\n");
+  printf("Prints details (yes/no)? ");
+
+  var details = false;
+  while (true) {
+    line = console.getline();
+    if (line === "") {
+      printf("Exiting. Please wait.\n");
+      return;
+    }
+
+    if (line === "yes" || line === "YES" || line === "y" || line === "Y") {
+      details = true;
+    }
+    break;
+  }
 
   var issues = [ ];
 
@@ -496,7 +555,7 @@ function main (argv) {
 
     printf("\n");
 
-    CheckCollection(collection, issues);
+    CheckCollection(collection, issues, details);
   }
 
  
diff --git a/js/server/bootstrap/module-internal.js b/js/server/bootstrap/module-internal.js
index 3e9ab5f0e0..f1ae61abea 100644
--- a/js/server/bootstrap/module-internal.js
+++ b/js/server/bootstrap/module-internal.js
@@ -189,7 +189,7 @@
   }
   else {
     internal.reloadAqlFunctions = function () {
-      internal.executeGlobalContextFunction("try { require(\"org/arangodb/ahuacatl\").reload(); } catch (err) { }");
+      internal.executeGlobalContextFunction("reloadAql");
       require("org/arangodb/ahuacatl").reload();
     };
   }
diff --git a/js/server/modules/org/arangodb/foxx/manager.js b/js/server/modules/org/arangodb/foxx/manager.js
index cb0f47f038..2506174888 100644
--- a/js/server/modules/org/arangodb/foxx/manager.js
+++ b/js/server/modules/org/arangodb/foxx/manager.js
@@ -957,7 +957,7 @@ exports.mount = function (appId, mount, options) {
   }
 
   if (typeof options.reload === "undefined" || options.reload === true) {
-    executeGlobalContextFunction("require(\"org/arangodb/actions\").reloadRouting()");
+    executeGlobalContextFunction("reloadRouting");
   }
 
   return { appId: app._id, mountId: doc._key, mount: mount };
@@ -1048,7 +1048,7 @@ exports.unmount = function (mount) {
 
   getStorage().remove(doc);
 
-  executeGlobalContextFunction("require(\"org/arangodb/actions\").reloadRouting()");
+  executeGlobalContextFunction("reloadRouting");
 
   return { appId: doc.app, mount: doc.mount, options: doc.options };
 };
@@ -1104,7 +1104,7 @@ exports.purge = function (key) {
   // remove the app
   getStorage().remove(doc);
 
-  executeGlobalContextFunction("require(\"org/arangodb/actions\").reloadRouting()");
+  executeGlobalContextFunction("reloadRouting");
 
   // we can be sure this is a database-specific app and no system app
   var path = fs.join(module.appPath(), doc.path);
@@ -1215,45 +1215,55 @@ exports.devTeardown = function (filename) {
 
 exports.appRoutes = function () {
   'use strict';
-
+  
   var aal = getStorage();
-  var find = aal.byExample({ type: "mount", active: true });
 
-  var routes = [];
+  return arangodb.db._executeTransaction({
+    collections: {
+      read: [ aal.name() ]
+    },
+    params: {
+      aal : aal
+    },
+    action: function (params) {
+      var find = params.aal.byExample({ type: "mount", active: true });
 
-  while (find.hasNext()) {
-    var doc = find.next();
+      var routes = [];
 
-    var appId = doc.app;
-    var mount = doc.mount;
-    var options = doc.options || { };
+      while (find.hasNext()) {
+        var doc = find.next();
+        var appId = doc.app;
+        var mount = doc.mount;
+        var options = doc.options || { };
 
-    try {
-      var app = module.createApp(appId, options || {});
+        try {
+          var app = module.createApp(appId, options || {});
 
-      if (app === null) {
-        throw new Error("Cannot find application '" + appId + "'");
+          if (app === null) {
+            throw new Error("Cannot find application '" + appId + "'");
+          }
+
+          var r = routingAalApp(app, mount, options);
+
+          if (r === null) {
+            throw new Error("Cannot compute the routing table for foxx application '" 
+                            + app._id + "', check the log file for errors!");
+          }
+
+          routes.push(r);
+
+          if (!developmentMode) {
+            console.log("Mounted foxx app '%s' on '%s'", appId, mount);
+          }
+        }
+        catch (err) {
+          console.error("Cannot mount foxx app '%s': %s", appId, String(err.stack || err));
+        }
       }
 
-      var r = routingAalApp(app, mount, options);
-
-      if (r === null) {
-        throw new Error("Cannot compute the routing table for foxx application '" 
-                        + app._id + "', check the log file for errors!");
-      }
-
-      routes.push(r);
-
-      if (!developmentMode) {
-        console.log("Mounted foxx app '%s' on '%s'", appId, mount);
-      }
+      return routes;
     }
-    catch (err) {
-      console.error("Cannot mount foxx app '%s': %s", appId, String(err.stack || err));
-    }
-  }
-
-  return routes;
+  });
 };
 
 ////////////////////////////////////////////////////////////////////////////////
diff --git a/lib/BasicsC/logging.c b/lib/BasicsC/logging.c
index 7000253ca3..c73d5909b7 100644
--- a/lib/BasicsC/logging.c
+++ b/lib/BasicsC/logging.c
@@ -511,7 +511,7 @@ static int GenerateMessage (char* buffer,
   m += n;
 
   // .............................................................................
-  // check if we must disply the line number
+  // check if we must display the line number
   // .............................................................................
 
   sln = ShowLineNumber;
diff --git a/lib/Rest/Handler.h b/lib/Rest/Handler.h
index 193dc27ea9..f21ff45643 100644
--- a/lib/Rest/Handler.h
+++ b/lib/Rest/Handler.h
@@ -98,10 +98,9 @@ namespace triagens {
                 }
 
                 case Handler::HANDLER_FAILED:
+                default:
                   return Job::status_t(Job::JOB_FAILED);
               }
-
-              return Job::status_t(Job::JOB_FAILED);
             }
 
             status_e status;
diff --git a/lib/V8/v8-utils.cpp b/lib/V8/v8-utils.cpp
index f755bb433a..23007b9a92 100644
--- a/lib/V8/v8-utils.cpp
+++ b/lib/V8/v8-utils.cpp
@@ -2275,7 +2275,7 @@ static v8::Handle<v8::Value> JS_Wait (v8::Arguments const& argv) {
   if (gc) {
     // wait with gc
     v8::V8::LowMemoryNotification();
-    while(! v8::V8::IdleNotification()) {
+    while (! v8::V8::IdleNotification()) {
     }
 
     size_t i = 0;