[jcifs] understanding server challenge change

[leostone]

hi, i have some trouble with changing server challenges.
i do SmbSession.getChallenge(ipOfTargetServer), then i feed this challenge 
to NtlmSsp.authenticate() wich returns an NtlmPasswordAuthentication object.
Next thing i do is creating a SmbFile using this NtlmPasswordAuthentication object
and do a SmbFile.connect(); 
The trouble is, on a WinXP target server this works, on a Win2K server the challenge
changes and i get a SmbAuthException from the SmbFile.connect() method.
Can someone explain what might be going on and how i could fix it.

Thanx alot
leo