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George Michaelson
Good find Shane! I read the documents, and It looks like there are still corner cases even in the business product where Microsoft say you should operate on an IPv4 binding. It interested me they went first to the managed business version of the service. Perhaps it has more constrained behaviours which make it easier for them to do the IPv6 port work here first, or expectations it runs on a narrower set of configurations and platforms. Given Apple's quite aggressive positioning on future IPv6 support needs for acceptance in App Store, Microsoft really had to move.