Comment 13 for bug 709642

Same here... I happens at least once or twice a week:

Jun 2 12:09:50 ed-linux acpid: client 1172[0:0] has disconnected
Jun 2 12:09:50 ed-linux acpid: client 1172[0:0] has disconnected
Jun 2 12:09:50 ed-linux acpid: client connected from 20696[0:0]
Jun 2 12:09:50 ed-linux acpid: 1 client rule loaded
Jun 2 12:09:51 ed-linux acpid: client connected from 20696[0:0]
Jun 2 12:09:51 ed-linux acpid: 1 client rule loaded

I'm running Ubuntu 12.04

$ dpkg -l | grep -i xorg
ii nvidia-current 295.53-0ubuntu1~precise~xup1 NVIDIA binary Xorg driver, kernel module and VDPAU library
ii nvidia-current-updates 295.49-0ubuntu0.1 NVIDIA binary Xorg driver, kernel module and VDPAU library
ii xorg 1:7.6+12ubuntu1 X.Org X Window System

$ uname -a
Linux ed-linux 3.2.0-25-generic-pae #40-Ubuntu SMP Wed May 23 22:11:24 UTC 2012 i686 i686 i386 GNU/Linux