duoshuo/oauth-proxy.php

<?php
if (empty($_GET['service']))
	return;

$endpoint =  (is_ssl()?'https':'http').'//duoshuo.com/login-callback/' . strtolower(trim($_GET['service'])) . '/';

unset($_GET['service']);

$callbackUrl = $endpoint . '?' . http_build_query($_GET, null, '&');

header('Location: ' . $callbackUrl, true);