If you have exchange 2007 or later and Entourage 2008 you can go download the update for Entourage called Entourage Web Services Edition.  (This includes AppRiver, I believe).  Make sure you have all the updates it requires.

However, I installed parallels, vista and outlook 2003.  Entourage 2008 cannot sync tasks with exchange 2003 without terrible and inconvenient work-arounds (like Missing Sync = Exchange to Mobile Device to Entourage).  This is definitely, not the best way to go.  I’ve been having copy-paste crash outlook several times.  I try and copy a section from my word document to outlook 2003, and I get the “this application has crashed” Vista window.

Aaargh.  At least its (most likely) fixed if you’re on exchange 2007 and Entourage 2008.


Sources:  Wikipedia, Usenet, Microsoft