Comment 59 for bug 43572

Roberto,
On my Dell D600, I could also use the Fn Keys to increase and decrease the brightness, and the brightness applet was not working before too. After I have performed the instructions, when I use those keys, it is behaving as before (from an end user point of view). I mean, if I press once on decrease, it decrease them once.
Also, the modification are easily undone. Basically, you install an updated version of the libsmbios, and by using Synaptic, it is pretty easy to restore the official version from Ubuntu 7.04.