Added sip_session script

Ignore-this: ec761aaa360f55fd13c5d8b4f2ecaae0

darcs-hash:20090907142709-1e3d8-90bd0ce0e6c5f90e157972c1e1bb8269e6402f1b
Fixed Session to timeout if a stream fails to start

Ignore-this: 53a2a52e2bed58661cd9e7b7e8190b5c

darcs-hash:20090907144308-1e3d8-52a30a9e50096c146d0b96d274c54bcdb92df339