Singleton with variable parameters

Hi guys, I am trying to generate an abstract Singleton class for use in arbitrary classes, like class Foo extends Singleton {} and generate a new class with Foo -> getInstance(); How can I manage to use this with an unkown number of parameters like Foo -> getInstance('a', 'b'); ? Something like "self::$instance = call_user_func (array(static , "__construct"), func_get_args());" instead of "self::$instance = new self;" doesn't work and an eval() is too slow. I hope you can help me. Thanks, Sebastian class Singleton { static private $instance = null; static public function getInstance() {

     if <http://www.phpbar.de/w/if>(null === self::$instance) {

self::$instance = new self; }

    return <http://www.phpbar.de/w/return>self::$instance;

} private function __construct(){} private function __clone(){} }