wrong xml post response when data already exists

when i post new resource twice (same request) behind mountpoint in json, i get first response: "204 No Content" and second response: "409 Conflict, Data already exists..."

when i try same in xml i get first response: "204 No Content" and second response: "204 No Content". it should be "409 Conflict, Data already exists..."

similar bug was here https://bugs.opendaylight.org/show_bug.cgi?id=1002