Outlook for MAC Users getting "Your password has expired",

I asked this in the Outlook for Mac forum but they kicked me over here.

http://answers.microsoft.com/en-us/mac/forum/macoffice2011-macoutlook/users-getting-your-password-has-expired-where-does/d385fc6a-973c-4012-bdb1-35f2627f1306

Any mailbox can be accessed via Outlook 2010 (Windows), OWA, or Outlook for MAC 2011.

Works fine on Outlook 2010 (Windows)
Works fine in OWA

Receive the message daily in Outlook for MAC 2011. Please explain how this is an exchange issue? If it was an exchange issue that same account would be getting prompted daily in 2010 or OWA.