Tive a ver e no index do phpnuke tem:
if ($httpref==1) {
$referer = $_SERVER["HTTP_REFERER"];
$referer = check_html($referer, nohtml);
if ($referer=="" OR eregi("^unknown", $referer) OR substr("$referer",0,strlen($nukeurl))==$nukeurl OR eregi("^bookmark",$referer)) {
} else {
$result = $db->sql_query("INSERT INTO ".$prefix."_referer VALUES (NULL, '$referer')");
}
$numrows = $db->sql_numrows($db->sql_query("SELECT * FROM ".$prefix."_referer"));
if($numrows>=$httprefmax) {
$result2 = $db->sql_query("DELETE FROM ".$prefix."_referer");
}
}
