Instructions how to do it from here:
How can I remotely enable Remote Desktop on Windows Server 2003?
With Remote Desktop on Windows XP Professional or Windows Server 2003 (in Windows 2000 Advanced Server, this feature was called Terminal Services in Remote Administration Mode), you can have access to a Windows session that is running on your computer when you are at another computer.What you need to do is create the new RDP listening port via the registry:
- Run REGEDIT on your XP workstation or on your Windows 2000/2003 Server.
- Click on File, then choose "Connect Network Registry".
- In the Select Computer search box either browse Active Directory to locate the remote server, or type its name in the dialog box.
- In the remote machine's registry browse to the following key: