I can confirm that bug was fixed on kernel 2.6.39.
To solve it on Natty:
sudo add-apt-repository ppa:kernel-ppa/ppa sudo apt-get update && sudo apt-get dist-upgrade -y
PS: You first need to uninstall fglrx restricted driver because it is not compatible with the new kernel.
I can confirm that bug was fixed on kernel 2.6.39.
To solve it on Natty:
sudo add-apt-repository ppa:kernel-ppa/ppa
sudo apt-get update && sudo apt-get dist-upgrade -y
PS: You first need to uninstall fglrx restricted driver because it is not compatible with the new kernel.