private function checkFunctions()
    {
        if (!function_exists('apache_request_headers')) {
            function apache_request_headers()
            {
                $arh = array();
                $rx_http = '/\AHTTP_/';
                foreach ($_SERVER as $key => $val) {
                    if (preg_match($rx_http, $key)) {
                        $arh_key = preg_replace($rx_http, '', $key);
                        $rx_matches = explode('_', $arh_key);
                        if (count($rx_matches) > 0 and strlen($arh_key) > 2) {
                            foreach ($rx_matches as $ak_key => $ak_val) {
                                $rx_matches[$ak_key] = ucfirst($ak_val);
                            }
                            $arh_key = implode('-', $rx_matches);
                        }
                        $arh[$arh_key] = $val;
                    }
                }
                return ($arh);
            }
        }
    }