If you're in Native mode - then you can't change the domain name unless you
upgrade to Windows Server 2003. If you have Exhange on the network
rendom.exe won't work (it might work in Exchange 2003, but I haven't tried
it yet). And you should know that renaming a domain is not a task you should
take light upon, even if there is a tool in Windows Server 2003.
http://www.microsoft.com/windows2000/downloads/tools/domainrename/
If you're in mixed mode, see this article:
http://support.microsoft.com/default.aspx?scid=kb;en-us;Q292541
You can define new UPN suffixes in AD Domains and Trusts snap-in, but you'll
need to change your current users to use it. This way users will believe
that you've renamed your AD and in most cases that's sufficient.
Regards,
/Jimmy
