Check if this is not the same issue as https://bugs.launchpad.net/ubuntu/+source/linux-restricted-modules-2.6.20/+bug/105928 - in which case the problem is solved if you install nvidia-glx-new. If someone finds a proper report on the issue of upgrades for people who have nvidia-glx installed, please link to it.
Check if this is not the same issue as https:/ /bugs.launchpad .net/ubuntu/ +source/ linux-restricte d-modules- 2.6.20/ +bug/105928 - in which case the problem is solved if you install nvidia-glx-new. If someone finds a proper report on the issue of upgrades for people who have nvidia-glx installed, please link to it.