Comment 19 for bug 277589

As I said it is very likely that the files on your computer and mine aren't at the same place,
but are you using an Ubuntu distribution, because it doesn't seem so, i just check the differents files in the x86 packages, and they should work.

1- So firstly we need to fix your hal, then reinstall the differents files :
sudo apt-get reinstall hal-info hal smartdimmer

2- we need to verify if different files exists
   # for the FN-Keys
ls -l /usr/share/hal/fdi/information/10freedesktop/30-keymap-module-sony-laptop.fdi
   # my modification on the method which should be used to change backlight (sony-nvidia)
ls -l /usr/share/hal/fdi/information/10freedesktop/10-sony-laptop-panel-mgmt-policy.fdi
   # for the scripts to change backlight (set and get them)
ls -l /usr/lib/hal/scripts/linux/hal-system-lcd-get-brightness-linux
ls -l /usr/lib/hal/scripts/linux/hal-system-lcd-set-brightness-linux

3- backup the scripts files and replace them with the ones that i gave you (attached with this post ):
#backup
cd /usr/lib/hal/scripts/linux/
sudo mv hal-system-lcd-get-brightness-linux hal-system-lcd-get-brightness-linux.back
sudo mv hal-system-lcd-set-brightness-linux hal-system-lcd-set-brightness-linux.back
#replace with the new ones
tar xvf a.tar
sudo cp hal-system-lcd-get-brightness-linux /usr/lib/hal/scripts/linux/hal-system-lcd-get-brightness-linux
sudo cp hal-system-lcd-set-brightness-linux /usr/lib/hal/scripts/linux/hal-system-lcd-set-brightness-linux
#make sure that they can be executed
sudo chmod +x /usr/lib/hal/scripts/linux/hal-system-lcd-set-brightness-linux /usr/lib/hal/scripts/linux/hal-system-lcd-get-brightness-linux
4- reboot your computer

I hope it works after this...If you are using a different distribution than Ubuntu or another version than hardy please inform me to check what is different.
PS : I tested nvclock instead of smartdimmer but it doesn't work because cannot use nvclock within an hal script ( it returns errors ).