Unfortunately, gnome-screensaver checks the X event queue to determine when an event occurs, and most joystick using programs in ubuntu use the kernel event interface (or legacy /dev/js0) from libsdl.
Regarding the mouse scroll, there is a limitation in X that only one client may trap button clicks at a time, so gnome-screensaver must ignore them in order to allow the program to see them. This is also annoying upstream (see src/gs-watcher-x11.c for the rant). ** Changed in: gnome-screensaver (Ubuntu) Status: Unconfirmed => Confirmed -- Joystick activity does not stop the screensaver https://launchpad.net/bugs/30378 -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs