Comment 3 for bug 911059

Also, can you confirm that the issue goes away by booting back into the latest Oneiric kernel(Which is in the proposed repository)? If so, the .deb for the kernel is available at:

https://launchpad.net/~canonical-kernel-team/+archive/ppa/+build/3061070/+files/linux-image-3.0.0-15-generic-pae_3.0.0-15.25_i386.deb