Win98 not seeing Windows 2000 Domain

What would cause a Win98 not able to see Windows 2000
domain? Other W2K workstation seem to see the domain and
login fine, but just one Win98 PC won't login. It says

"No domain server was available to validate your
password. You may not be able to gain access to some
network resources."

I added the Win98 computer name to the active directory.
Allowed pre w2k machine to logon that account. The user
name and password seem to be correct because it works on
a W2K professional PC. I even try to logon w/ the
administrator account, but no luck.

From the Win98 PC I can ping the domain controller PC IP
just fine. I can even go outside the LAN and to the
internet and browse just fine.

What seem to be the problem? Any idea?

Thanks!