Very slow login authentication with XP

I am setting up a W2K server which has 2 win89 boxes and 1 XP box as clients. For some reason after joining the XP box to the domain the login process is painfully slow somtimes taking as much as 4 minutes. The two win89 boxes login in very fast. I have setup this same scenario at home and get the same type of slow login response. The w2k server is a duel PIII 800 with 512 megs ram. I can only think that there is something in particular with XP that I am unaware of. Both XP box and server 2000 have the latest patches. The setup at work and the setup at home have some hardware differences so it leads me to believe that its something with XP
Help