I'm trying to register a Cisco 1760 on a Cirpack SoftSwitch using the SIP protocol.
I can correctly register the lines, but there is no way to unregister them afterwards. When I try, I get a "400 Bad Request" answer from the SS.
My guess: the Via: field in the REGISTER message shows port 5060, while the SIP packets come from a different port.
Is there any way to force the sip-ua to use the 5060/udp as the suorce port for sending SIP packets to the softswitch?
P.S.: example capture file in attachment