Surpress StumbleUpon url and replace them with actual ones from your StumbleUpon likes feed

stumbleupon_likes_rss_parser.php

<?php

function stumble2url ($url) {
    $doc = new DOMDocument;
    
    if (!@$doc->loadHTMLFile($url))
        return null;

    return ($iframe = $doc->getElementById('tb-stumble-frame'))
        ? $iframe->getAttribute('src')
        : null;
}

libxml_use_internal_errors(true);
set_time_limit(300); // 5 min

$rss_feed_address = "http://www.stumbleupon.com/rss/stumbler/bdelespierre/likes";

$rss_feed_dom = new DOMDocument;
$rss_feed_dom->load($rss_feed_address);

$rss_xpath = new DOMXPath($rss_feed_dom);

foreach ($rss_xpath->query('//channel/item') as $item) {
    $link = $rss_xpath->query('./link', $item)->item(0);
    $guid = $rss_xpath->query('./guid', $item)->item(0);
    $desc = $rss_xpath->query('./description', $item)->item(0);

    if (!$link || !$stumble_url = $link->nodeValue)
        continue;

    if (!$real_url = stumble2url($stumble_url))
        continue;

    $link->nodeValue = $real_url;
    $guid->nodeValue = $real_url;
    $real_desc_data  = str_replace("href=\"$stumble_url\"", "href=\"$real_url\"", $desc->nodeValue);
    $real_desc_cdata = $rss_feed_dom->createCDATASection($real_desc_data);
    $real_desc       = $rss_feed_dom->createElement('description');
    $desc_parent     = $desc->parentNode;

    $desc_parent->removeChild($desc);
    $desc_parent->appendChild($real_desc);
    $real_desc->appendChild($real_desc_cdata);
}

PHP_SAPI != 'cli' && header("Content-Type: application/rss+xml");
echo $rss_feed_dom->saveXML();