Windows 98SE unexpectedly logs off Windows 2003 standard server

Here is a challenge for someone as it's the major headache of my life.

What I've done so far....

Opportunistic locking disabled on the server.
SMB signing is not a requirement.
Read ahead cache is disabled.

For the life of me I can not find the Directory Services client on the
Windows 2003 CD or anywhere else, so I used the Windows 2003 client on
the Windows 2000 sever CD.

I'm going to try obtain the updated DS services from Microsoft, ref:
http://support.microsoft.com/default...b;en-us;323466

Maybe that will cure it?

Ths issue is that the `Client for Microsoft Networks` is not
configured to validate the login against the domain controller.
Deliberate move as the Win9x had problems authenticating. A few drive
letters are mapped to UNS paths on the server.

All of a sudden, without warning the Win98-SE station's application
screws up and I get a few hundred of the following in the security
event log ...

Event Type: Failure Audit
Event Source: Security
Event Category: Account Logon
Event ID: 680
Date: 01/03/2004
Time: 15:19:27
User: NT AUTHORITY\SYSTEM
Computer: MELOLINE1
Description:
Logon attempt by: MICROSOFT_AUTHENTICATION_PACKAGE_V1_0
Logon account: JACK
Source Workstation: \\ACCOUNTS
Error Code: 0xC000006A

So, I go to the computer and for sure the application has failed. So,
I open explorer and just click on the mapped drive letter and get a
directory listing, return to the server, examine the log and see ...

Event Type: Success Audit
Event Source: Security
Event Category: Account Logon
Event ID: 680
Date: 01/03/2004
Time: 15:22:52
User: MELOLINE\JACK
Computer: MELOLINE1
Description:
Logon attempt by: MICROSOFT_AUTHENTICATION_PACKAGE_V1_0
Logon account: JACK
Source Workstation: \\ACCOUNTS
Error Code: 0x0

A second identical `Success Audit` follows the first and the
application that failed will load again and function.

Can I find a solution to this? Can I f***! Can anyone help, I've run
out of every possible idea on how this can be fixed.

Is this a fault on the server or workstation?

I ask this from the following lesson I learnt. When the Novell servers
were present, the Boss's computer would not save a word document with
a space in the file name and I wasted a week trying to fix his
computer, but his computer was not the problem. By chance I discovered
a patch to apply to the Novell server. I applied the patch and the
fault on the Boss's computer was banished forever.

Somone help! Please! I'm begging!!!