I started using the override feature when I upgraded to 1.4.3 thinking this would preclude having to modify core code for upgrades made in the future. I have two files (AddressController.php and AuthController.php) that worked to override the 1.4.3 core. These files eliminated the normalization of the US address (it forced all caps). I can go back in and modify the core code in the controller directory to verify that it works, but I'd rather do the override. Below is the code in my override/controller/AddressController.php that works in 1.4.3 but not in 1.4.4
This is a Prestashsop forum thread dealing with this topic.