Shared folder missing

I work in a school district, and we just upgraded our
servers from NT to 2000. Since we upgraded, our Windows
98 machines cannot see the user folder on the new server.
Our 2000 and XP machines can see the folders on the new
server with no problem, it only seems to be our 98
machines. If a user logs in on a XP or 2000 machine,
they can see their folder on the server, if the same
user logs in on a 98 machine they can't see their folder,
and worse yet cannot access the server at all.

Any help would be greatly appreciated.

Thanks

Rich