I use a Mac at home and Windows at work, and was wondering how to get my iPhone synced to my work (outlook) calendar as well as my Mac. Finally last night I tried setting up Entourage to access my work email via IMAP, and it also downloaded my calendar (I was not expecting this). So since I had my calendar, I decided to try syncing my iPhone to see if it worked, and sure enough I now have all of my work calendar entries. I had previously tried using mail.app to access my work email but it was dog slow and very unpredictable, so I deleted the account. Entourage is much faster and works much better for this particular account, but it did not work well with my .mac account, so I use mail.app for that. I will probably just leave Entourage up in the background all of the time to keep my calendars synced.