> curl --data @- -X PUT '-H if-match: "30050093"' --dump - http://localhost:8529/document/73482/30050094
{ "World" : "Hallo" }

HTTP/1.1 412 Precondition Failed
content-type: application/json; charset=utf-8

{
  "_rev": 30050094,
  "_id": "73482/30050094",
  "error": true
}