I have a H323 trunk connected from CCM (version 4.1) to a third party PBX. We use this trunk for 4 digit dialing. I have setup CAC to only allow 10 calls at a time on this trunk, this works great. The 11th call is blocked. But now I need to figure out how to setup something similar to AAR so that the 11th call is re-routed over the PSTN.

I do not believe that AAR can be configured to work since the device I am calling is not a Cisco device, is that correct?

I thought about adding the PSTN gateway to the route list however that will not work since any digits that I insert on the route list will be applied to both the IP trunk and the PSTN trunk.

What if I create two different routes and route-list (one for IP and one for PSTN) for the PBX extensions, each route would have a different partition and both partitions would be available to all users. Then I would have the flexibility of inserting PSTN digits on the PSTN route list. Would that work?

The only question is: If CCM detects that there is not enough bandwidth to send the call via H323, is CCM smart enough to send the call to the next route in the route table (in this case the same extension number but with a different partition) or will the caller get the not enough bandwidth message. Can someone verify?