netbeans autocompletion when using singleton to retrieve object instead of new operator?

Question

when i use the 'new' operator to instantiate a class, netbeans has no problem to autocomplete the members of the object.

$instance = new Singleton();
$instance-> // shows test() method

but when i use a singleton to retrieve an object it cannot autocomplete the members in the object retrieved.

the getInstance code looks like this:

public function test() {
    echo "hello";
}

public static function getInstance() {
if ( ! is_object(self::$_instance)) {
    self::$_instance = new self();
    self::$_instance->initialize();
}
return self::$_instance;
}

so i use:

$instance = Singleton::getInstance();
$instance-> // no autocompletion!

does anyone have the same problem?

how do i work around it?

thanks!