Actually figured it out when solving another issue for someone else.
Delete all messages you can or save them
Open Desktop Manager
I always tell people to do a backup first
Then go to Backup and Restore - Advanced
In the right hand window (Device Database)
scroll down to messages and highlight
then click on clear button.
That should fix it. Messages you can't delete gone http://www.blackberryforums.com/imag.../icon_wink.gif