Problem: Profile synchronization was not running between MOSS and WSS for a specific web application.
Solution: Even though the profile imports were running, the SharePoint profiles had a person's old display name instead of their AD display name. The following is from MS support:
1) Stsadm –o sync –listolddatabases 0
2) Stsadm –o sync –deleteolddatabases 0
3) Stsadm –o sync –synctiming m:1
4) Stsadm –o sync –sweeptiming m:1
5) Stsadm –o sync –excludewebapps “”
The last command was the one that reset the profile synchronization so all web apps were again included.