Just upgraded from SLED10 SP1 to SP2 on my Dell laptop, and wanted to
give the compiz desktop effects a trial run.

Working fine for several hours, happily spinning the cube, then I
pressed Ctrl+Alt+Del (so I could lock the screen) and got a
segmentation fault:

Sep 1 14:52:52 picard kernel: compiz[8126]: segfault at
0000000000000020 rip 00000000004197a0 rsp 00007fff8d974a20 error 4
Sep 1 14:52:52 picard gdm[8038]: Error reinitilizing server
Sep 1 14:52:55 picard gdm[16310]: Display :0 is busy. There is another
X server running already.

Has anyone else encountered this fault? Is there a fix?

It happened several times yesterday, each time I lost my session and
had to re-login. How do I trace the cause of the problem?