Currently we return '412 Precondition Failed', but this status should only be returned if a precondition that is given in a request-header field evaluates to false. Since this is not the case for group creation/rename the correct response status is '409 Conflict'. Change-Id: I2811756b1421de4f7a6d07eb881667b16ecdc66a Signed-off-by: Edwin Kempin <edwin.kempin@sap.com>