Input Cleaning

[Kirk Y]

Okay, somebody save me from myself. I can't get my request to clean.

$pw = $vbulletin->userinfo[password];
$string = md5($pw);
$h =& $vbulletin->input->clean_gpc('r', 'h', TYPE_UINT);

if ($_REQUEST['do'] == 'unsub')
{
   if (md5($h) === $string)
   {
       echo 'correct';
   }
   else
   {
       echo 'incorrect';
   }
}

Now, if I go ahead and just use $_GET instead of cleaning, it works fine -- but it fails if I try to use the cleaned var. What am I missing here?