After update Xorg server crashes

[Simion Onea]

Hi!
Today I updated my system. The following packages were installed:
Sep 18 07:55:50 Installed: lyx-fonts-common-1.6.4-1.fc11.noarch
Sep 18 07:55:56 Updated: glib2-2.20.5-1.fc11.x86_64
Sep 18 07:55:58 Updated: glib2-2.20.5-1.fc11.i586
Sep 18 07:56:04 Updated: gtk2-2.16.6-2.fc11.x86_64
Sep 18 07:56:06 Updated: crda-1.1.0_2009.09.08-2.fc11.x86_64
Sep 18 07:56:06 Installed: lyx-cmsy10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:06 Installed: lyx-esint10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:06 Installed: lyx-cmmi10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:07 Installed: lyx-eufm10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:07 Installed: lyx-msbm10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:07 Installed: lyx-msam10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:07 Installed: lyx-cmr10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:08 Installed: lyx-cmex10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:08 Installed: lyx-wasy10-fonts-1.6.4-1.fc11.noarch
Sep 18 07:56:08 Installed: lyx-fonts-compat-1.6.4-1.fc11.noarch
Sep 18 07:56:14 Updated: phpMyAdmin-3.2.2-1.fc11.noarch
Sep 18 07:56:17 Updated: gtk2-2.16.6-2.fc11.i586
Sep 18 07:56:24 Updated: coreutils-7.2-4.fc11.x86_64
Sep 18 07:56:27 Updated: util-linux-ng-2.14.2-10.fc11.x86_64
Sep 18 07:56:38 Erased: mathml-fonts

I have rebooted my system and after that I cannot log-in to my system
using the graphical interface. After I hit my username and enter the
password the screen turns black for a brief and then the login screen
appears again.
I switched to a text terminal and checked the "/var/log/messages".
Here are the related lines:
Sep 18 08:20:47 TestField pam: gdm-password[2308]:
pam_unix(gdm-password:session): session opened for user simion.onea by
(uid=0)
Sep 18 08:20:48 TestField pulseaudio[2784]: pid.c: Stale PID file, overwriting.
Sep 18 08:20:48 TestField kernel: SELinux: initialized (dev fuse, type
fuse), uses genfs_contexts
Sep 18 08:20:48 TestField pulseaudio[2852]: pid.c: Daemon already running.
Sep 18 08:20:49 TestField kernel: Xorg[2234]: segfault at 0 ip
00000000004e8e0b sp 00007fff6d026658 error 4 in Xorg[400000+1b6000]
Sep 18 08:20:49 TestField pam: gdm-password[2308]:
pam_unix(gdm-password:session): session closed for user simion.onea
Sep 18 08:20:49 TestField gnome-keyring-daemon[2617]: dbus failure
unregistering from session: Connection is closed
Sep 18 08:20:49 TestField kernel: [drm] DAC-6: set mode 1280x1024 16

As you can see Xorg segfaults.

Has enybody encountered such an error?
What can be done in this case?

Regards,
Simion Onea.