Comment # 9 on bug 980521 from Dr. Werner Fink

(In reply to Martin Szulecki from comment #7)

Please could you add two lines

 printenv
 set -x

after the comment

 #
 # Check if a dbus is required for e.g. plain xdm sessions
 #

in /etc/X11/xdm/sys.xsession and attach the users X session log with curruent
environment as well as with the resulting trace of the following shell
commands.