Quote Originally Posted by dswartz View Post
Uh, I don't have an ATA (I'm running asterisk, remember?)
oops, sorry, I did not have enough cafein

I still have my doubt that it is a NAT problem

anyways, do sip trace to see if asterisk supports session timer and who's responsible for the refresh

if you want, you can post the trace here (after some editing to protect the identity of the innocent)