opera, chromium and kwin effects crash X

I’ve a strange problem after an update a few days ago (2012-09-17)
I remember that xorg-x11 was updated to version 7.6_1.12.3-1.5.1

When I try to start Opera or Chromium or enable the kwin effects (openGL-Compositing?) X crashes and I am back at the login screen.

I even tried to downgrade xorg-x11-server and xorg-x11-Xvnc to version 7.6_1.12.3-1.2.3 but this didn’t solve the problem.
Should I try an older version of X?
I cannot remember which version I used before and there might be another cause of my problems…

Some information:

0: /usr/bin/Xorg (xorg_backtrace+0x36) [0x564616]
1: /usr/bin/Xorg (0x400000+0x168349) [0x568349]
2: /lib64/libpthread.so.0 (0x7f7fcd651000+0xf140) [0x7f7fcd660140]

Segmentation fault at address (nil)

Fatal server error:
Caught signal 11 (Segmentation fault). Server aborting

I’m using tumbleweed, twinview, NVIDIA-Linux-x86_64-304.32

Has anyone an idea?

seems to be the same problem: http://forums.opensuse.org/english/get-technical-help-here/applications/478732-x-org-crashes-since-update-21-sept-2012-a.html