I have Unity 4.0.4 connected to a Exchange 2003 server. When caller from the PSTN leave a voice mail, users are able to listen to the messages without any problems. However, when voice mails are left by internal users (IP phone to IP phone), the caller gets the VM greeting and is able to leave a message but the called party does not get a WMI indication; on logging on the Unity voice mail box, it tells him that there are no new messages! Where should I start looking? I have restarted the call manager/unity and exchange servers to no affect.