Eternity should work out-of-the box with the standard Gnome Screensaver and KScreensaver packages. However, if you run Xscreensaver you'll need to do a little bit of configuration...
You should have a file called .xscreensaver in your home directory. If you don't, then running xscreensaver-demo and making a small configuration change will generate one for you. Once you have it, add the following lines to the end of the "programs" section (depending on which Eternity plugins you have installed):
- "Eternity" eternity-screensaver \n\ - "Eternal Ubuntu" eternal-ubuntu \n\ - "Eternal Damnation" eternal-damnation \n\ - "Eternal Ubuntu Studio" eternal-studio \n\
Also, make sure you're running at least version 0.2 of the Eternity screensaver and plugins.
That's it! Enjoy.
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