I have installed Ubuntu 12.04. I uninstalled gnome screensaver and got Xscreensaver working almost perfect. The only problem I am having is when my laptop is running Xscreensaver for more than 5 minutes key strokes or touch pad are not recognized so I have to hard reset my laptop to be able to work because no matter what I do Xscreensaver do not come off.... and I know that my laptop is not suspended or locked because those options are set to OFF, but if I disable the Xscreensaver through caffeine it sat off and my laptop never get the problem described.
Last time I got this situation I was listening music with Rythmbox and I tried to turn down the volume when the screen was already "possessed" by Xscrennsaver and nothing happened, so no keystroke, no touch pad, no volume control, nothing worked....had to hard reset my laptop once more.
Will not use Xscreensaver until there is a solution for it, I like it very much but will not risk my hard drive. Any one know how to solve this?