<Fn><F2> and <Fn><Fn><F3> without effect

[farinet at arcor.de]

lubuntu-users-request at lists.ubuntu.com:
> Curiously, for brightness, 'xbacklight -inc 10' or so does not have any
> effect increasing brightness ( 'xbacklight -dec 10' works as aspected).
> If i use 'xbacklight -dec -10' it increases backlight brightness. Not
> really logical ... ;-)

Small add on: After suspend-to-ram the backlight shortcuts do not work
at all ...