I installed Mint 5 on my Acer 4520 laptop. I can't hibernate my laptop, because it does just like being suspended. All things are still on, just screen goes blank, and power LED is blinking yellow every second. And it can't be woken from hibernate. The only thing works is forcing it to shut down by pressing power button 4 secs.
The same thing happens with Suspend. Screen goes blank, and can't revive it.
I've seen a similar posting here viewtopic.php?f=49&t=1647
but the hibernation problem got no solution.