I am using the Zimbra iSyn Connector version 4.5.441 . I'm trying to sync my Address Book data with my Zimbra web client. But I kep getting the following notice:

! The iSync connector was unable to sync because it couldn't create a valid session. This is typically due to a bugin Apple's iSync. The problem can be fixed in one of three ways.

1. Restart iSync....
2. Log out...
3. Reboot...

None of these things seem to solve the problem and I keep getting the notice.