[SR-Users] mid-registrar example

Hi everyone I'm trying to implement OpenSIPS-like mid registrar functionality using UAC module Up to now, I was simply performing authentication on my kamailio instance, saving to local domain and forwarding the request to another proxy I'd like to lower the number of requests sent to this other proxy, by forwarding only a few of the incoming requests. This is not a problem to do, but then comes the handling of expiration. If the SIP UAC is disconnected, the registration expires on my kamailio instance, but I don't know how to correctly notify the other proxy on the unregistration (I was trying to build and send a request using uac_send_req(), but this is useless as I can't set the CSeq value) While looking for a solution to my problem, I discovered that OpenSIPS had a mid registrar module doing exactly what I'd like to do (according to the documentation at least). I also saw old messages on this list that it was possible to achieve the same result with UAC module on kamailio In particular, I don't see why (or if) I need to populate the uacreg table. I don't see why it should be necessary, and it would have a great impact on performance to use a db for this matter. I also don't need (I think) to have different local and remote from and to URIs I think I need to build the a new REGISTER request using $uac_req, but I don't see any contact header in the outgoing request, despite having set reg_contact_addr value Thanks for any clue you could give me