How to config a IPv4-over-IPv6 tunnel?

[Bear]

hi,
I am a administrator of a school network. My school has already deployed a pure-IPv6 network with NAT-PT. But there are massive applications cannot support IPv6, so these applications cannot work at all. Now I *DO NOT* wanna build a dual-stack network, because if I build a dual-stack network, IPv6 will have no users, all users will use IPv4 to communicate with the websites which in IPv4 network. So I wanna build a tunnel, the start-point is client, the end-point is a special dual-stack machine. Also, a sock5 proxy is all right. Could you tell me how to do this? thx!

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Bear
2010-06-16