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,
'autoStart'=>true,
'timeout' => 1209600,
'cookieMode' => 'only',
),