just add this 2 lines in xorg.conf , section Device :I did, and he's right, as you'll see below. Not to bite the hand that feeds me, but I hope this fix is the 'correct' fix, and that it's included in any future releases. It's so simple (at least for ATI cards like mine, a 9600).
Option "AddARGBGLXVisuals" "true"
Restart your X , and problem with Compiz/Beryl fixed :)
The first screen capture shows three gterms and the system monitor. What's really nice is that the gterms have true transparency. If you enable gterm transparency without Compiz, the gterm simply maps the desktop image into its background. But now I can see everything under the gterm. More than just pretty eye candy, I can keep track of other dynamically updating applications (such as top, or something like Gmail in Firefox). Another nice feature is the three dimensional shadowing that also helps to distinguish windows on the desktop. It really adds a level of polish to the whole affair.
This is an example of Expose-like behavior, which I definitely like. Move the mouse to the upper right corner, and the overlapping windows resize and reorganize into smaller versions of themselves, making for easier selection. Again, very nicely done.