CDbHttpSession timeout ignored

Both CDbHttpSession and CHttpSession seem to be ignoring the timeout value and garbage collect data after a fairly short time (less than 12 hours).

What could be the problem?

        'session' => array(

		'class'=> 'CDbHttpSession',

		'autoCreateSessionTable' => true,


		'timeout' => 1209600,

           	'cookieMode' => 'only',


I haven’t checked this but look at the php.ini settings - there might be something overriding it.