[Users] NOTIFY message required fields ??

Is the field "Content-length" a required field in a NOTIFY message? I see that it is part of almost every message from OpenSER except the NOTIFY message. This is causing some issues with Gaim SIMPLe interface which processes the header based on the header string "Content-Length". Note Gaim does not care about the value associated with the header string just the fact that the string "Content-Length" exists. Therefore, since OpenSER isnt sending the string, Gaim is core dumping. FYI on the core dump. Yes, Gaim still has a bug on how it is processing what it sees as unknown SIP messages which actually is causing the core dump, the real problem is the fact that Gaim is processing the header, expecting to see the field "Content-length". So before I report this to Gaim as a bug, I wanted to get insight into whether the field is a required field. Thanks......