function rfc_date() {
        $tz = date("Z");
        $tzs = ($tz < 0) ? "-" : "+";
        $tz = abs($tz);
        $tz = ($tz/3600)*100 + ($tz%3600)/60;
        $date = sprintf("%s %s%04d", date("D, j M Y H:i:s"), $tzs, $tz);
        return $date;
   }