V2 on Vm Server
V2 client on NT 4.0

Four days ago our client received the following error:  ANR0484W Protocol
violation detected.  The message books reads:

ANR0484W Session session number for node node name (client platform)
       terminated - protocol violation detected.
       Explanation:  The server ends the specified session because a
       communications protocol error by the client has been detected.
       System Action:  The server ends the client session.
       User Response:  Examine the client message to determine the
       problem.  Correct the programming error in the client program.  If
       the client program has been provided by IBM, and the error cannot
       be isolated and resolved, contact your service representative.

Doesn't help me a whole lot.  (Sorry, IBM, but your error message
explanations for ADSM leave a whole lot to be
desired.)
His session was terminated and he hasn't been able to establish an NT Service
session since although there is no problem communicating via the GUI
interface.  When he attempts to connect the error log shows the following
error:

 ANS4017E Session Rejected
   TcpOpen    TCP/IP error connecting to server.
    SessOpen  Failure in Communications Open Call rc: -50

Does anybody ideas on what might be happening here or what I can try to
correct the problem.  At this point his NT service just keeps trying to log
on and failing.  This is the client who's platform is showing up as "Password
Check" that I sent the note out about earlier.

Thanks for your thoughts and
suggestions.