I used:
$auth->setStorage(new Zend_Auth_Storage_Session('admin'));
$result = $auth->authenticate($adapter);
...


Than later after success authenticate:
$data = $adapter->getResultRowObject(null, 'password');
$auth->getStorage()->write($data);

Can I use following to access the saved data?

$auth = new Zend_Session_Namespace('admin');
hello, $auth->admin_firstname


admin_firstname is a column in the admin table.