Cannot open a VNX session on the remote server

[Ferry Toth]

I am using freenx from the freenx-team stable (lucid) ppa on my Natty server (version is 0.7.3.git110520.3884279-0ubuntu1ppa4).

This works fine for KDE4.

I also run a virtual kvm windows machine on the same server which I can access fine using vncviewer (without password). And in the past also from freenx, with a small glitch: I get the choose existing session dialog, showing 2 sessions both of which didn't work. When I created a new session I got the windows machine.

Currently I still get to the point of the existing session dialog, but creating a new session times out.

The session log shows:
Usage: vncpasswd [FILE]
       vncpasswd -t

VNC Viewer Free Edition 4.1.1 for X - built Apr 9 2010 15:52:37
Copyright (C) 2002-2005 RealVNC Ltd.
See http://www.realvnc.com for information on VNC.
vncviewer: unable to open display "nx/nx,options=/home/ferry/.nx/C-ferry-quad-2000-E83C59CE6C43464F3DCD320A1C1B04A6/options:2000"

All ideas welcome,

Ferry