Brightness control is dead after install Nvidia Drivers

[Pedro Rodrigues <pedro.rodrigues.86@gmail.com>]

Hey,

I've just installed the Nvidia drivers on my Debian, 
however, after i do it, the laptop brightness control doesn't work 
anymore...

When i press the keys, i see the brightness bar, however, the brightness stays at maximum.

I've used the following commands to install the drivers.

apt-get update
apt-get install nvidia-kernel-source
m-a a-i nvidia-kernel-source
apt-get install nvidia-glx
apt-get install nvidia-xconfig
nvidia-xconfig
apt-get install nvidia-settings

The Laptop is a Sony Vaio VGN-FE21B with a Nvidia Geforce 7400

Can you help me?

thx in advance.