If I do the following: GW calls SIP proxy : works However, I'm trying to forward (stateful) a call to a SIP Proxy, but it seems that it's failing. This is my scenario: GW -> SER calls SIP proxy: fails. This is my ser.cfg if (uri=~"^sip:123") { t_relay_to_udp("Proxy_IP", "5060"); break; }; I thought that it's the same as a GW, but it seems that I'm wrong. Help is appreciated :)