[cvsnt] Authentication failure with SSPI

[Kevin K]

CVSNT Version: 1.11.1.3 (Build 65)
WinCVS 1.3
OS: Windows2000

Scenario:
I'm trying to perform a checkout. I get this error message on all 3 of my
repositories: 
cvs checkout -P WebSite (in directory c:\development)
cvs [checkout aborted]: unrecognized auth response from nts0986: cvs
[server aborted]: Authentication failed

I can successfully commit any changes to the repository. In my WinCVS,
under Admin\General I have:
Authentication: sspi
Path: \WebSite
Host Address: nts0986
User name: kkolle
CVSROOT: kkolle at nts0986:\WebSite

I've searched some of the archives and haven't found the answer just yet,
I'm sure the answer is out there somewhere.
What are some things I could try?

Thanks for your help!
Kevin