xserver crashes when playing video with mplayer

[JR]

whenever I play a video with mplayer (also tried mplayer2) the xserver crashes. I already stopped kdm, executed startx from the console, opened a xterm inside and play the video -> crash.
when I play the video on the console (outside X) with DISPLAY correctly set, the video plays (actually I asume so as I can't see it, but I hear the audio). when I switch to the VT running X then, the xserver crashes.

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: xserver-xorg 1:7.6+10ubuntu1
ProcVersionSignature: Ubuntu 3.2.0-18.28-generic 3.2.9
Uname: Linux 3.2.0-18-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 1.94.1-0ubuntu1
Architecture: amd64
Date: Wed Mar 7 20:56:45 2012
InstallationMedia: Kubuntu 9.10 "Karmic Koala" - Release amd64 (20091027)
ProcEnviron:
 LANGUAGE=
 TERM=xterm
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: xorg
UpgradeStatus: Upgraded to precise on 2012-03-06 (1 days ago)

[JR (juergen-richtsfeld)]

the log showing the crash

[JR (juergen-richtsfeld)]

I forgot to mention that (of course) all of that worked with 11.10 and I can play the video on 12.4 using vlc.

[JR (juergen-richtsfeld)]

the problem can be worked around by using -vo gl in mplayer.

when using default output in vlc, the same crash happens.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.