Our organization is planning a major upgrade this summer. We currently run Sun One Messaging server for email. We have Unity 4.1(1) partnered to an Exchange 2003 box for voice mail with about 400 users. The system is setup for unified messaging but we are only using it for voicemail at the moment.
This summer we are installing Exchange 2007 which will be our enterprise mail solution dropping the Sun product. We are very small staffed and just don't have time to upgrade Unity during the same time frame.
Once Exchange 2007 has been installed and all 400 user's mailboxes from Exchange 2003 have been moved to 2007, can Unity 4.1 still operate partnered to our current Exchange 2003 server? Will messages flow from the partner 2003 to the 2007 mail store without having to upgrade Unity to 5.x?