I can confirm this, I have the same issues with a Lenovo x200 intel x4500HD graphics card, jaunty with 2.6.31-020631rc3 kernel and various stable and unstable xserver-xorg-video-intel drivers. It is exactly as Sandro has described, sometimes crashing X, or throwing up an error, or giving the GLXBadDrawable error.
I can confirm this, I have the same issues with a Lenovo x200 intel x4500HD graphics card, jaunty with 2.6.31-020631rc3 kernel and various stable and unstable xserver- xorg-video- intel drivers. It is exactly as Sandro has described, sometimes crashing X, or throwing up an error, or giving the GLXBadDrawable error.