do not enable SIPTracer by default in logstate

darcs-hash:20090326081202-b2873-94f0e30b4a9e49ef6cd87415c0e8d11d23433d64
add -c, --trace-sip, --trace-pjsip options to sip_session.py (from audio script)

darcs-hash:20090326081326-b2873-1d66b93b46b310f1f84ff6dd483e5376bcea331b