(PHP):

$sign_arr= array(
    'uid' => $uid,
    'sid' => $sid,
);
$m_key = "1234567890";
ksort($sign_arr);
$str = '';
foreach ($sign_arr as $k => $v) {
    $str.=$k.'='.$v.'&';
}
$str = $str.$m_key;
return md5(md5($str));