# Upgrading from Kohana If you were using 3.3.x version, there are 4 breaking changes that may affect you, be aware. - **Kohana_Kohana_Exception**, all functions that received parameter Exception $e have been replaced to just $e. If you are extending the class verify you have the same. - **Kohana_URL**, now function site has a new parameter `$subdomain = NULL`, if you are extending the class and this function add it. - **Module encrypt**, now encryption works as a module, if you are using new Encrypt or similar you need to enable the module in your bootstrap ex: `'encrypt' => MODPATH.'encrypt',` - **MySQL driver** has been removed. If you are still using it, please install MySQLi driver and then edit your `config/database.php` and then set as `'type' => 'MySQLi'` ## New modules included - Encrypt (separated from system) - Pagination