Novell client causes winlogon.exe error and BSOD

After installing the Novell Client for XP drivers we now cannot logon to the LAN normally.
The error msg when rebooting is :
SAS window: Winlogon.exe - Application Error
The instruction at "ox58foc236" reference memory at "0x00000014".  The memory could not be "read".  Click on the OK button to terminate the pgm.
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The next screen after clicking on the OK button is BSOD ...
STOP: C000021a {Fatal System Error}
The winodws logon process system process terminated unexpectedly with a status of 0xc00000005 (ox0000000 ox0000000)
The system has been shut down
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If I logon to Workstation Only on the Novell client, system boots to windows and maps drives OK .. but we then get another error message.
Winlogon.exe
Winlogon.exe encountered a problem and needs to close.  We close this screen OK.
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Now when we right click on My Network Places, then click on Novell Login, enter the login details for Novell and it works OK .. maps drives OK and all is well.

If I REMOVE the Novell Client software then ALL of these error mesages go away .. but we obviously cannot connect to our NOVELL server.

ANY SUGGESTIONS on what may have caused this problem or how to fix it will be greatly appreciated!  This software has been working for a long time and suddenly it's no longer working properly.

Thanks,
Shane