private static function mhtmlCompatable() { if (!isset(self::$mhtml)) { $ua = @$_SERVER['HTTP_USER_AGENT']; $mhtml = false; $mhtml_compatable = "/MSIE [67]\\.0/"; preg_match($mhtml_compatable, $ua, $matches); if ($matches) { $mhtml = true; } self::$mhtml = $mhtml; } return self::$mhtml; }