I have Unity 3.x running onsite which allow me to add subscribers from a separate exchange server 5.5. The users can log in and register, however they can't get any message (voice mail and unified messaging) and there is no MWI. The Unity server has been working fine in the past but recently exchange server play up where the Internet Mail Connector unable to start after a reset. However if Unity is disconnected from the mail server the mail connector can start again. There is something going on between the two but I don't know of a test that will show me what happen ie whether exchange did receive any message.
