[SR-Users] Problems with TCP

Hi, our customers are using mostly UDP but some of them want to use TCP. The problem is, I get various TCP errors in kamailio log and I do not understand what they mean 1) ERROR: <core> [tcp_main.c:4130]: connect <customerIP:port> failed This means kamailio is trying to connect with TCP to the customer ?? 2) WARNING: tcp_do_connect <customerIP:port> : could not find corresponding listening socket for IPaddress , using default... ( where IPaddress is kamailio physical IP address) Kamailio has one virtual IP address (heartbeat IP address) and one physical. It listens on the virtual IP address but I do not understand why it is trying to use the physical IP address ? I was investigating this thing because the BYE message is not being relayed if the TCP is used (everytime the 2. error message is printed), so that's why I have to understand what it really means... And the last question, 3) If kamailio is relaying the traffic to the PSTN gateway, and the customer is using TCP, kamailio uses TCP as well for connecting to the PSTN gw. Is this behaviour normal ? I would expect that customer -- TCP --> kamailio --- UDP --> GW, and not customer -- TCP --> kamailio --- TCP --> GW, Thanks, Mino