Session Class - Wiered Behavior

[eluser]Twisted1919[/eluser]
Thats's simple . is the classic case :

Code:

if($this->database->login($username,$password) == TRUE)
{
$session_data = array('logged_in'=>TRUE , 'username'=>$username);
$this->session->set_userdata($session_data);
header('location:/user_panel.php');
die();
}
else
{
//Show some error
}

Where database is a model and login is a method that checks if the username and the password do match into database .
Is this the data you are asking for ?