Previously I had created a role and added a user. The user waited several weeks
to try to login and now is receiving a message that his role is no longer
valid. When I login to administer the site his role is not listed and when I
re-created the role I can't add him because his name is 'grayed' out and
indicates that he is currently assigned to the previous role.

Has anyone else had this problem? How can I fix it?