lo he intentado con el siguiente código:
Cita: <?php
header("Content-type: text/html; charset=utf-8");
$rss_forosdelweb = file_get_contents("http://www.forosdelweb.com/external.php?type=RSS2&forumids=18");
$xml = new SimpleXMLElement($rss_forosdelweb);
echo "<span style='font-weight: bold; font-size: 26px;'>" . $xml->channel->title . "</span><br /><br />";
foreach($xml->channel->item as $item){
echo "<a href='".$item->link."'>".$item->title."</a> -> " . nl2br(htmlentities($item->description, ENT_QUOTES, "UTF-8")) . "<br /><br />";
}