I thought the tunneling only applied to XP. The way I understood it was that IPV6 in XP was a tunnel protocol that went through IPV4 and in Vista it became a stack instead of a tunnel. So Vista either connects direct IPV6 to IPV6 or IPV4 to IPV4 and without a supporting router the transit is lost if a downgrade to IPV4 can't be performed. Is this wrong?

FDB