I have found that if I join a workgroup machine to the domain, and the same name already exist, in the Win2k3 AD domain, the computer account will be taken over by the machine being joined to the domain. I see this as a possible catastrohpic issue/feature. If by chance, someone had a workgroup machine with the same name as an exchange, smtp, or a CEO machine, and then joined it to the domain, the existing account would be taken over by the machine being joined to the domain. When the original domain machine rebooted, it would be unabel to login to the domain.