Ubuntu 9.04 Exchange IMAP - Thousands of calendar appointments!

[jerkychew]

I'm running Ubuntu 9.04 against Exchange 2003 using the "Exchange IMAP" account type. I logged in today and had about 20 appointment reminders. There seems to be a UI issue where the dismiss all button doesn't appear until I dismiss several of the appointments, although that's not the issue I'm posting about.

My Outlook calendar only has a few appointments in it, and none for today. Opening my calendar in Zimbra shows thousands of appointments! We have a lot of calendars published to public folders, is it possible that the appointments are being pulled from there? I don't want to open the appointments as some of them are for executives and I'd prefer not to open anything I'm not supposed to.