I do believe that Windows XP comes with a telnet server, you just have to enable the telnet server. If you go to control panel, then to administrative tools, then to computer management, then to services and applications, click on services you can scroll down to telnet.
If you start this service it should allow clients to telnet to the machine......I don't know if that is such a good idea, but you can if you would like. Erik Rudnick, CCIE No. 9545
mailto:erik@kuriosity.com