Yes...a DC will have different rules (even on a 2008/2003.
You'll first need to set this:
http://technet.microsoft.com/en-us/library/cc785165%28WS.10%29.aspx
Then:
You'll need to change the Domain Controller policy setting as well:
RDP - Allow log on through Terminal Services
This security setting determines which users or groups have permission
to log on as a Terminal Services client. By default, on domain
controllers only Administrators have permission.
But you also shouldn't be allowing non-admins access to a domain controller...but you can determine your level of risk here...