CDbHttpSession error: CDbConnection failed to open the DB connection: could not find driver


I’m trying to use CDbHttpSession but when I change it in my main.php from CHTTPSession I get the following error in Yii:

I have PDO drivers successfully installed on my Linux server and I can connect to the database anyway, I only get this error when I try to use CDbHttpSession.

I also allowed the PDO extensions in my php.ini:

I have php5-mysql installed and I restarted the apache2 of course.

I have the following in my main.php:

'components' => array(



	'session' => array(

	   'class' => 'CDbHttpSession',





	'db' => array(

		'connectionString' => 'mysql:host=localhost;dbname=databasename',

		'emulatePrepare' => true,

		'username' => 'username',

		'password' => 'password',

		'charset' => 'utf8', 

		'tablePrefix' => '',






Thanks in advance for your helping answers.