login script problem when connecting to

Ive just attatched a Windows XP Pro workstation to a Windows NT 4 Server domain and when i logon as an existing user, which attempts to run the login script that is located on the server, the script runs and i get all the mapped drives i get when i log onto a win98 machine. However, i get the access denied message when i attempt to enter the mapped drives. I can get access to the the shared folders through network places no problem. Is there a login script compatibility issue with XP Pro and WinNT server? Any help would be appreciated.

Many thanks

Tim.