iwl3945 wifi working on unbuntu hardy

I have an acer 2920 with T7500 processor (dual core 2.2ghz)...

after a lot of jumps around several forums I have collapsed here the working solution:

From here:
install backports for drivers

sudo apt-get install linux-backports-modules-hardy

create as super user:

sudo gedit /etc/modprobe.d/blacklist-ipw3945

write this line inside:

blacklist ipw3945

--- restart ---

to test if it is working try with:

sudo iwlist wlan0 scan

probably it is not enough, if you have errors during scanning, you have to do:

sudo gedit /etc/modprobe.d/iwl3945

write inside it the following lines:

alias wlan0 iwl3945
options iwl3945 disable_hw_scan=1

--- restart --- again