Zend_Loader::loadClass('Zend_Session');
Zend_Loader::loadClass('Zend_Session_Namespace');

in bootstrap 
Zend_Session::start();
in indexcontroller

$sess = new Zend_Session_Namespace('user');
$sess->info = array( 'id' => '2',
'username' => 'David',
'pass' => '132');
Zend_Session::rememberMe(3600); // remember me for one hour
$sess->lock(); 
(you probably could use this when authenticating the data)

Zend_Session::namespaceGet('user'); //Experimental, haven't even tested it