for::getHttpHeader

public function getHttpHeader($header)
    {
        // are we using PHP-flavored headers?
        if (mb_strpos($header, '_') === false) {
            $header = str_replace('-', '_', $header);
		$header = mb_strtoupper($header);
        }

        // test the alternate, too
        $altHeader = 'HTTP_' . $header;

        //Test both the regular and the HTTP_ prefix
        if (isset($this->httpHeaders[$header])) {
            return $this->httpHeaders[$header];
        } elseif (isset($this->httpHeaders[$altHeader])) {
            return $this->httpHeaders[$altHeader];
        }

        return null;
    }