no execution of Xsession

When I try to log in using the graphical (Gnome) login screen, I get the
message "cannot start the session due to some internal error". This also
happens for a failsafe session. I can, however, login on runlevel 1 (add
kernel parameter 1 upon booting) and then enter runlevel 5 by using "startx"
(although many menu-icons seem not to be able to invoke programs anymore).
Below are messages from 1. /var/log/messages, 2. /root/.xsession-errors and
3. /var/log/Xorg.0.log. I am running a FC4 2.6.11-1.1369 setup. The first
file cearly indicates the error "could not exec /etc/X11/xdm/Xsession
default". Have the messages under 2. got to do with it? I appreciate your
suggestions if you know what goes wrong, Marc

1. /var/log/messages file:
"Feb 26 14:39:19 comp2 kernel: [drm] Initialized drm 1.0.0 20040925
Feb 26 14:39:19 comp2 kernel: ACPI: PCI Interrupt 0000:00:02.0[A] -> Link
[LNKA] -> GSI 11 (level, low) -> IRQ 11
Feb 26 14:39:19 comp2 kernel: [drm] Initialized i915 1.1.0 20040405 on minor
0:
Feb 26 14:39:19 comp2 kernel: mtrr: base(0xe8020000) is not aligned on a
size(0x258000) boundary
Feb 26 14:39:29 comp2 gdm(pam_unix)[2478]: session opened for user root by
(uid=0)
Feb 26 14:39:31 comp2 gdm[2549]: session_child_run: Could not exec
/etc/X11/xdm/Xsession default
Feb 26 14:39:43 comp2 gdm(pam_unix)[2478]: session closed for user root
Feb 26 14:39:43 comp2 kernel: mtrr: base(0xe8020000) is not aligned on a
size(0x258000) boundary
Feb 26 14:39:48 comp2 kernel: audit(:338560): major=252 name_count=0:
freeing multiple contexts (1)
Feb 26 14:39:48 comp2 kernel: audit(:290349): major=113 name_count=0:
freeing multiple contexts (2)"

2. /root/.xsession-errors
"etc/X11/gdm/PreSession/Default: Registering your session with wtmp and utmp
/etc/X11/gdm/PreSession/Default: running: /usr/bin/X11/sessreg -a -w
/var/log/wtmp -u /var/run/utmp -x "/var/gdm/:0.Xservers" -h "" -l ":0"
"root"
SESSION_MANAGER=local/comp2.homenetwork:/tmp/.ICE-unix/5021
Unable to open desktop file
applications:///Office/redhat-word-processor.desktop for panel launcher:
Error reading file 'applications:///Office/redhat-word-processor.desktop':
File not found
Unable to open desktop file
applications:///Office/redhat-presentations.desktop for panel launcher:
Error reading file 'applications:///Office/redhat-presentations.desktop':
File not found
Unable to open desktop file
applications:///Office/redhat-spread***.desktop for panel launcher: Error
reading file 'applications:///Office/redhat-spread***.desktop': File not
found

** (nautilus:5144): WARNING **: Can't go Up from here. The UI should have
prevented us from getting this far.

(nautilus:5190): libgnomevfs-CRITICAL **: file gnome-vfs-uri.c: line 916
(gnome_vfs_uri_unref): assertion `uri != NULL' failed

** (nautilus:5144): WARNING **: destroyed file still being monitored"

3. /val/log/Xorg.0.log: "audit: rejected client 5 from localhost"


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