Comment 6 for bug 107115

I can confirm the black screen on log out using the resricted driver with an ati radeon xpress 200m.

Editing /etc/X11/gdm/gdm.conf so AlwaysRestartServer=true is a valid workaround. I cannot speak to issues with hibernation but can also second the fact that this is a bug that was introduced some time during the Feisty beta, as logging out did work once without a workaround.

For what it's worth, I suggest this is an important bug, as the ati radeon xpress 200m is an all too common card and the problem a real show-stopper.