The underlying issue with most of these "Caller ID" problems is that the Mediation server strips any Calling Party Name information from the incoming call as OCS currently is programmed to not trust that information, as it's not secure. It's the same thing as being able to send an SMTP message to someone with anything you want in the From: field. But since R2 now supports secured SIP connections with certified gateways/IP-PBX we may see that behavior change in the future as the Mediation Server could be told to trust the source, meaning no need to strip that CPN info. I think MS would be smart to include that, but who knows if that is on their radar or not for future releases.
Jeff Schertz, PointBridge | MVP | MCITP: Enterprise Messaging | MCTS: OCS