Roaming profiles in w2k/nt40

I have problems with users who have their roaming profiles on old NT4.0 server, wich i want to move to the new w2k server.
I haved moved the folders and give them the right security. But evere time they try to log in
they get an error message saying. “The system cannot find your domain e.t.c.

Any solutions anyone.????

Morten