Exchange 2k Licensing Problem

While viewing the event log, I noted that a critical error was reporting that a license violation was occuring. After following the instruction, I noted that former employees user accounts where still holding onto the exchange license. These users have been removed from AD for over 2 months. Does anyone know why? It would make sense that once you remove the user account from the AD it would revoke the license. I have resolved this by manually revoking the licenses on these former users. Is there a setting in Exchange that will sync the AD with the licensing in exchange

 

How long are you keeping deleted mail?? My guess is that as long as you have deleted mail in the IS, then the license is "in use".