Win XP Professional

I got 2 workstation running WinXP Professional SP1 and this 2 workstation has been logged into Win2k server with administrator rights.

this 2 workstation can link each other, can ping and see each other, but when double click on their computer name, it appear ” network path not found. please contact your administrator”. that means i even cant shared printer or files. why??

But when i installed one Win98se and logged into the server, this workstation can go into that 2 workstation on Win XP Prof. Win XP bug or what?