How to specify RDP port number??????????

 How to specify RDP port number??????????

I'm trying to connect a T50 over the internet to a Windows 7 VM thru a CISCO firewall using port 6150....
and its not working........... I don't see anyplace to enter the port number........ my windows 7 workstation connects ok, and I can connect the T50 to other sites that use the default port 3389..... So how does one specify the RDC port number?????????