Hello Paolo!
> I went back to debian sid after using ubuntu for a few months. So far,
> i've been able to configure my thinkpad t42p to resemble some ubuntu
> goodies except for fn-f12: nothing happens when i hit it, as supposed
> to hibernate using ubuntu. I have verified that echo disk >
> /sys/power/state just works though. Any hint how ubuntu did it?
> Also, how do i enable graphical notification of screen brightness in
> gnome when i use the appropriate fn-key combination, similar to
> ubuntu? Thanks.
You have to install the acpi and acpid stuff. AFAIK it knows this
shortcut. You can see it in the acpid log file.