Changed logging messages in sip_audio_session.py

darcs-hash:20090407164849-58103-feab6d3d4e40bbfb0e0ad9df9b2153b3a404653d
Changed logging messages in sip_message.py

darcs-hash:20090407164858-58103-abd28d09b79abf0c40736012b4f2a41be05fc6bb