Sony Vaio VGN-SZ79GN adjusting brightness
I recently bought a Sony Vaio VGN-SZ79GN and installed Ubuntu 8.04. I am trying to move to Ubuntu as my main desktop environement, but I am faced with several problems, the most major of which is the brightness adjustment which doesn't work at all (always stays at max), and the screen of the laptop is too bright to comfortably work like this in most environments, also it drains the battery unnecessarily.
When adjusting the brightness through any of the methods I have found on the net, or via the standard buttons for that, the brightness value in /sys/class/backlight/sony/brightness changes accordingly, but the actual screen brightness stays the same.
Your help is highly appreciated!
Thank you in advance!