% telnet -6 www.v6pc.jp 80
Trying 2001:380:62c:20:122:1:4:51...
Connected to www.v6pc.jp.
Escape character is '^]'.
GET /jp/index.phtml HTTP/1.1
Host: www.v6pc.jp
HTTP/1.1 200 OK
(略)
<div class="header_protocol"><img src="/images/common/protocol_ipv4.gif" alt="You are now using IPv4"></div>