※aws4class.phpファイルの244行目から著名認証のプログラムを加えます。

242			if ($this->ResponseGroup)
243			   $this->baseURL .= '&ResponseGroup='.$this->ResponseGroup; // この下に加える
244		}

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242			if ($this->ResponseGroup)
243			   $this->baseURL .= '&ResponseGroup='.$this->ResponseGroup;

	$secret_key = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx"; // シークレットアクセスキー
	$ret_char = "\n";
	$url_array = parse_url($this->baseURL);
	parse_str($url_array[query], $param_array);
	$param_array[Timestamp] = gmdate("Y-m-d\TH:i:s\Z");
	ksort($param_array);
	$str = "GET".$ret_char.$url_array[host].$ret_char.$url_array[path].$ret_char;
	$str_param = "";
	while( list($key, $value) = each($param_array) ){
		$str_param =
			$str_param.strtr($key, "_", ".")."=".rawurlencode($value)."&";
	}
	$str = $str.substr($str_param, 0, strlen($str_param)-1);
	$signature = base64_encode( hash_hmac("sha256", $str, $secret_key, true) );
	$this->baseURL = "http://".$url_array[host].$url_array[path]."?".$str_param."Signature=".rawurlencode($signature);

		}