My laptop is not able to recover from suspend and hibernate

I have a acer aspire 5750G laptop. I am running ubuntu 11.04. The uname -a reads the following: > Linux admin-Aspire-5750G 2.6.38-13-generic-pae #56-Ubuntu SMP Tue Feb 14 14:32:30 UTC 2012 i686 i686 i386 GNU/Linux Whenever the wakes up from suspend or hibernate, it shows a blank screen. Same thing happens when the lid is closed and opened later. What should I do to fix this? **Edit#1:** I have the pm-utils installed. I could suspend using pm-suspend. When I press any key to wake up, the machine wakes up but hangs. It does not respond to any keyboard or mouse keys after wake up. What could be wrong here?