[Serusers] UAC UDP to Proxy TCP... Problem

Hi everybody, I have a UDP2TCP problem with Ser. (0.9-4) The UACs connected to my SER Proxy are all UDP. When I use some carriers to connect them to PSTN The Carrier Proxy / GW could talk UDP or TCP. It depends on the destination. Each time the Carrier GW want to talk TCP, the contact field is correct and contains the 'transport=tcp' mention. all seems to be correct and, after a complete reading about this subject in the list, I trust that using t_relay() must do the right translation and send response via TCP to the Carrier GW when this one is transport=tcp declared. If I Check the message for an Ack or a BYE sent to the TCP GW the uri is correct : the transport=tcp is added. Request-Line: ACK sip:50033299848400@200.1xx.xx.xx:5060;transport=tcp SIP/2.0 I have red that this is sufficient to let SER understand that it must be sent via TCP. unfortunately, this message is ent thru UDP. May I force with a t_relay_to_tcp ? As this case depends on the carrier dynamic routing it could be complicated because of the need to know the destination to script t_relay_to_tco(uri, port)... If anybody has the trick or any advice... Other thing related, when TCP is the transport mode from the Carrier GW and I forward staefully to the UAC (Asterisk) the call failed between Asterisk as UAC and the carrier GW. I wondering it was because the Carrier Gw didn't receive an ACK TCP from my server.. Well I'm completely lost... as you can feel with my message... I need Help.. But don't cal me Harry ;) Regards, Christian Thomas