I have teredo working so that I can ping VM via ipv6, squid3 is also working fine but only via ipv4. I made two endpoints (tcp and udp) to the proxy (port 8888) on the Azure site. What should I do now to make the port accessible via ipv6?
Teredo is not suitable for server/service deployment. If you want your server to be reachable over IPv6 then either get native connectivity, or else use a reliable tunnel from i.e. tunnelbroker.net.