Any sniffer will sniff the packet u just want one which will pick out rtp streams. These streams arent much use I mean they are voice…what u wanna be able to do is to redirect this stream to a store file or a player, and then listen right 🙂
The rest of the voice packets are just gonna be the SIP (assuming sip) headers and stuff, which arent the most exciting things in life to listen to.
nehow if u wanna listen, then google. cause everytime I post a name here, it denies my post, but it all out there
prozac–use it, and then surf 🙂