[FreeNX-kNX] black screen after authentication

[Michael Oevermann]

Hello,

I am having problems getting freenx running in CentOS 4.5  i386_64. I know this is not a new problem, however, I havn't found a solution in all the postings I found on the web.
I did exactly what is supposed to work and described in detail at
http://wiki.centos.org/HowTos/FreeNX
After doing a standard install I can connect to the server with nxclient without problem but I get only a window with a black screen. In the files
	.nx/S.../session  and errors
I see the warning
	Warning: Unrecognized session type 'unix-gnome'. Assuming agent session. The same happens with KDE. 
With the command
	nxloadconfig --check
I get the output

Warning: Could not find nxdesktop in /usr/bin. RDP sessions won't work.
Warning: Could not find nxviewer in /usr/bin. VNC sessions won't work.
Warning: Invalid value "APPLICATION_LIBRARY_PRELOAD=/usr/lib/libX11.so.6.2:/usr/lib/libXext.so.6.4:/usr/lib/libXcomp.so.2:/usr/lib/libXcompext.so:/usr/lib/libXrender.so.1.2".
/usr/lib/libX11.so.6.2 could not be found. Users will not be able to
run a single application in non-rootless mode.
Warning: Invalid value "COMMAND_FOOMATIC=/usr/lib/cups/driver/foomatic-ppdfile"
         Users will not be able to use foomatic.
Warning: "/usr/lib/cups/backend/nxipp" is not executable.
         Users will not be able to enable printing.
Warning: "/usr/lib/cups/backend/smb" is not executable.
         Users will not be able to enable printing.
Warning: Invalid value "COMMAND_START_CDE=cdwm"
         Users will not be able to request a CDE session.
Warning: Invalid cupsd version of "/usr/sbin/cupsd". Need version 1.2.
         Users will not be able to enable printing.
Error: Could not find 1.5.0 or 2.[01].0 or 3.0.0 version string in
nxagent. NX 1.5.0 or 2.[01].0 or 3.0.0 backend is needed for this
version of FreeNX.
  Errors occured during config check.
  Please correct the configuration file.

The libraries are definitely not where nx looks for them - they are
located under /usr/lib64/NX/lib (and symlinks under (usr/lib/NX/lib).
What is going wrong here? I also tried to use nxconfig with --setup-nomachine-key with the same error messages and warnings as in the log files

Does anyone has an idea to solve the problem? If its only a path problem to the libs, where are the configuration files and which variables do I
need to set? Is a simple nxconfig with "corrected" settings enough to
set up the server correctly?

Many thanks for help

Michael