All hotkeys of the laptop works but brightness ones. I have to change brightness level manually, but if I hit the key nothing happens. I suppose is a kernel issue. The fact that the minimun level of brightness is zero is a driver issue, I think. I don't know if it is a configuration problem or a bug. I will report all needed info.
please attach the acpidump output and the output of "grep . /sys/class/backlight/*/*". BTW, how do you change the brightness level manually?
ping...
Bug closed as there is no update from the bug reporter for 3 months. please feel free to re-open once you can provide the information requested in comment #1.