Hi Steve,

Just came across a situation where cifs client was failing to mount a
share with ntlmssp served by cifsd based server.
The server is misbehaving in that is should have set the
EncryptionKeyLength to zero (when offering extended security).
Regardless though, a windows client will happily continue whereas the
cifs client will return IO(5) error. Looking in the MS-SMB spec 
(2.2.4.5.2.1) mentions

"ChallengeLength (1 byte): When the CAP_EXTENDED_SECURITY bit is set,
the server MUST set this value to zero and clients MUST ignore this value."

I attach a patch to cifs for this

thanks,

Noel