To reproduce, hold Control + Mouse Button (try left, middle, and right) anywhere in an xterm (the real one from X.org) or go through the menues of the xboard program (if you have it).
Affected are both RHEL5 and RHEL6 for quite some time now. Other X drivers work correctly on both platforms.
Also properly working is Nvidia driver 295.71.
I have attached a screenshot of a broken xboard menue. And sooner or later, the missing bits come up all over the place, see second screenshot. Taken with el5/fvwm, el6/gnome+compositing and either 331.20 or 331.38.
nvidia-bug-report.log.gz (54.9 KB)