I thought that this would have been a done deal but it looks like it is not.
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interesting looking links at the bottom.
"NAT64 is an mechanism to allow IPv6 host to communicate with IPv4 servers
DNS64 Combined with NAT64, this allows hosts connected only via IPv6 to access other hosts only connected by IPv4."
So these "solve" the *opposite* problem to the one posed by the Original Poster.
i.e. IPV6 internally and IPV4 on the internet.
Oh dear. If there is NO effective IPV6 externally and IPV4 internally scheme there is going to be a LOT of work for network guys for years to come.
I've not read this yet but the title sounds promising. IPv6 Transition Tutorial by Cisco Systems
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