I am just joining the PBXnSIP community and have the same question as jholland posted back in March.
In our hosted environment we are seeing that about 40% of our calls are intercom calls or supervised transfers and would like to keep the local LAN (intercom) calls RTP media local with RE-INVITEs after the PBXnSIP has handled the call signaling to the registered end point. This would save of the bandwidth requirements between the hosted site and the remote location. It should also be the method for any group paging feature.
We are using OpenSER as the front end proxy between the remote location end points and PBXnSIP. The end points of course are registering with PBXnSIP and not OpenSER so I would be looking for a solution within PBXnSIP to support RE-INVITEs between end points registering from the same remote locations.
Again, I am new to PBXnSIP so please forgive any ignorance. But I have abandoned all hope for * in a hosted environment. SIP stack blows....
Krom