Opauth is a PHP library for providing a multi-provider authentication system. It works with stand-alone PHP and frameworks like Yii, Zend, Symfony, CodeIgniter and CakePHP. Features of Opauth:Supported services:- LinkedIn- Google- Twitter- Facebook- OpenID- OAuth Requirements:- PHP 5 or Higher What's New in This Version:- Fixed session to check for session_id() instead of $_SESSION.