I am wandering how to configure the CMS in order that 2 internal numbers calling each other from the same PBX (dialing the DID, instead of the extension #), could be routed internally via the CMS, instead of calling the PSTN, and returning.
You would need to set the pbx numbers up on the hop off directory associated with the trunk connected to the pbx. You then need to enable hairpinning so that the call will trombone on the same trunk.