Refactored sip_auto_publish_presence

Ignore-this: f11a6f8058f8fce7cc2704cf3eab046e

darcs-hash:20090329231106-1e3d8-272c0ed914666b53fd5d19d092588aae4c95adfb
Refactored sip_publish_presence

Ignore-this: f49c7178ba83c96a9f7b30f7451d2a22

darcs-hash:20090329231111-1e3d8-bc4f6a0fdc774e616c8c88d15ea0e54c8d28481e