Steps to reproduce:

Run any OpenGL application (e.g. glxgears). When left untouched it runs OK. Grab
the app's window and move it a accross the screen => crash.

Using Xorg from Mandriva 2006.0 32-bit distribution. Tested with nVidia gr. card
(see the log below) usign native nv driver, also tested with ATI X300 using both
native radeon driver and ATI's binary fglrx driver. (I think it is not driver
related.) However it works when using a 64-bit distribution (tested on ATI Mob.
Rad. 9600 with both native radeon and ATI's binary drivers).

Here is the backtrace (I'll try to attach the complete log):

Backtrace:
0: /etc/X11/X(xf86SigHandler+0x88) [0x8089668]
1: [0xffffe420]
2: /usr/X11R6/lib/modules/extensions/libGLcore.so [0xb7a3a78a]
3:
/usr/X11R6/lib/modules/extensions/libGLcore.so(_swrast_clear_depth_buffer+0x31d)
[0xb7a906ed]
4: /usr/X11R6/lib/modules/extensions/libGLcore.so(_swrast_Clear+0x34b) [0xb7a8b42b]
5: /usr/X11R6/lib/modules/extensions/libGLcore.so [0xb7b29123]
6: /usr/X11R6/lib/modules/extensions/libGLcore.so(_mesa_Clear+0x179) [0xb79d3989]
7: /usr/X11R6/lib/modules/extensions/libGLcore.so(glClear+0x26) [0xb79a7246]
8: /usr/X11R6/lib/modules/extensions/libglx.so(__glXDisp_Clear+0x1f) [0xb7be93ef]
9: /usr/X11R6/lib/modules/extensions/libglx.so(__glXRender+0xcf) [0xb7c018bf]
10: /usr/X11R6/lib/modules/extensions/libglx.so [0xb7c04344]
11: /etc/X11/X(Dispatch+0x15e) [0x80ca21e]
12: /etc/X11/X(main+0x407) [0x80d73f7]
13: /lib/tls/libc.so.6(__libc_start_main+0xd0) [0xb7d6be40]
14: /etc/X11/X [0x8070121]

Fatal server error:
Caught signal 11.  Server aborting