Removed sipsimple.core.send_message

darcs-hash:20090424155525-58103-0219644b166773efbcd4f4899f242599cdedac59
Fixed missing import after classproperty move

Ignore-this: d8baa1f36a748b37ec53cd822d6b715a

darcs-hash:20090425094012-1e3d8-bd4a03bdeab96333a9b0e6c93d0ae31e57f78be2