Windows98 boxes can't find domain

[mrbspc]

Folks,


I setup a Win server 2003 AD. Everything
was fine. Then about a month later, I changed the
site to a full class C network from a .192 net.
After the netmask update, I got strange DNS errors and had to rebuild DNS. Now my Windows 98 boxes cannot find the
domain controller for auth. They can ping the server
by name and can access restricted shares, so authentication
must be happening.
What am I missing?

Thanks,
B