Comment 1 for bug 107115

I can confirm the black screen (not the freezing system) upon log-out and switch user behaviour - a few days ago... but strangely, that behaviour vanished again after a lot of messing around with my fglrx settings and attempt to get my ati radeon xpress 200m to run with desktop effects or compiz (not succeeded).

I found to my horror that this 'black screen on log-off/switch user' issue has been replaced by 'hibernation not working' !! Too bad, because I used hibernation more than log-off/switch user :(