Comment 58 for bug 186382

If you are using nvidia 173.08, you can download a fixed libnvidia-wfb.so.173.08 from

http://people.freedesktop.org/~aplattner/wfb/Linux-x86/libnvidia-wfb.so.173.08

and replace /usr/lib/xorg/modules/libnvidia-wfb.so.173.08 with this version.

lrwxrwxrwx 1 root root 23 2008-04-22 10:29 libnvidia-wfb.so.1 -> libnvidia-wfb.so.173.08*
-rwxr-xr-x 1 root root 270552 2008-04-26 20:09 libnvidia-wfb.so.173.08*

lrwxrwxrwx 1 root root 18 2008-04-26 20:24 libwfb.so -> libnvidia-wfb.so.1*
-rw-r--r-- 1 root root 197363 2008-04-15 19:41 libwfb.so-dist

That works for me.