[OpenSER-Users] UDP/TCP failover in OpenSER

Hello list, I have several questions about the support of TCP in OpenSER in general, and about the switch/ failover from UDP to TCP in particular. In my setup, I have several SIP clients registered to a single OpenSER, and they exchange presence messages on a peer-to-peer basis. When the presence document is complex, the size of the message sent exceeds a given limit, and I want my message to be sent over TCP. My clients are registered on the OpenSER, and the REGISTER has been sent over UDP. From now, when client A sends a NOTIFY using TCP to client B, the message is transported over TCP from A to the OpenSER, and is transported over UDP from the OpenSER to B. So here are my questions : - How can I tell OpenSER to relay the message to B using TCP ? - Do I have something particular to do while registering to tell OpenSER that the client is listening in UDP and TCP ? Thank you in advance for your answers, Antoine