[cvsnt] Hit following error, "Couldn't authenticate with lock server: FAIL Case insensitive locks no longer supported"

[lang qiu]

I have set a CVSNT on my local machine, when I used tortoise cvs to access 
it, I hit the following error,
*cvs.exe [import aborted]: Couldn't authenticate with lock server: FAIL Case 
insensitive locks no longer supported *

*Error, CVS operation failed

In C:\DOCUME~1\xxx\LOCALS~1\Temp\TortoiseCVS make new module temp\: 
"C:\Program Files\TortoiseCVS\cvs.exe" "-q" "import" "-m" "" "inv2" 
"tcvs-vendor" "tcvs-release" 
CVSROOT=C:\hosting*
Any idea?
 The cvsnt version I used is 2.5.02.
The tortoisecvs version is 1.8.18