Comment 9 for bug 56436

The fix did not make it into Edgy. You have to

mv
/usr/share/gnome-screensaver/themes/electricsheep.desktop /usr/share/applications/screensavers/electricsheep.desktop

Also, to fix bug #2379 you must edit /usr/share/applications/screensavers/electricsheep.desktop

Change the line:

Exec=electricsheep --root 1

to

Exec=electricsheep --root 1 --zoom 1

After all this it likely still won't work due to bug #5823. At a terminal you can fix 5823 by substituting --root 1 with --mplayer 1, but this doesn't work in the .desktop file.