Network Disconnecting in win98

I'm a network administrator in mwm co. with Win2003
Server as PDC and a network with two segment.
Each segment of my network connect to one NIC in PDC and
Win2003 route between segments.
Now I hahve a problem with Win98 workstations in my
Nettwork:
When some users login to PDC and try to access resources
such as shared folders, printers or etc... , PDC dont
permission on this resources and the user have to logoff
and then access to resources.Why ...?
Thanks

i have been having this same problem with both windows 2003 standard and the 2003 small business server. if i get s solution i will let you know. no one seems to have an answer for this yet