upgrading calendars message upon startup

My iCal keeps starting up on its own as I turn on my MacBookPro. I have selected that no apps fire up at start up but iCal seems to ignore that. Then I get a window with a progress barber pole saying "Upgrading Calendars" without any buttons or any way to x out of it. It stays on indefinitely... and is very annoying

anyone else have this issue?

Thanks