Comment 17 for bug 262408

Best way to go currently is to install (manually compile) the keyfuzz program and put

echo "786616 99" | keyfuzz -s -d /dev/input/by-id/usb-Apple_Inc._Apple_Internal_Keyboard___Trackpad-event-kbd

in your /etc/profile for instance. This maps Alt-Eject on a typical Apple Macbook Pro (mine is mid-2010, 6,2), to the Alt-SysRq combination.