Okay, since this is blocking iCal syncing, you'll want to carry out the steps in this
post.
I did some forum reorganization recently, and just realized that moving a thread un-stickies it; I've re-stickied the thread that post was in. Sorry it was so hard to find!
If the steps in that post don't resolve the issue, you'll want to email our
support ninjas so they can help.