Windows XP A to Z - http://www.softwaretipsandtricks.com/windowsxp
Changing the listening Port on Remote Desktop
http://www.softwaretipsandtricks.com/windowsxp/articles/131/1/Changing-the-listening-Port-on-Remote-Desktop
Super Admin
 
By Super Admin
Published on 02/23/2005
 
You can use the Remote Desktop feature in Windows XP Professional to connect to your computer from another, remote computer.

Changing the listening Port on Remote Desktop

WARNING: The Remote Assistance feature in Windows XP may not work properly if you change the listening port. To change the port that Remote Desktop listens on:

Start Registry Editor (Regedt32.exe).


Locate the following key in the registry:


HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\TerminalServer\WinStations\RDP-Tcp\PortNumber
On the Edit menu, click Modify, click Decimal, type the new port number, and then click OK.


Quit Registry Editor.


NOTE: When you try to connect to this computer by using the Remote Desktop connection, you must type the new port.

Update: I forgot to inform you that you need to add this to the default.rdp file for the XP terminal client... Add this line anywhere in the file.
server port:i:your port number
ie server port:i:21