IPv6 Addresses causing Exchange Relay whitelists to fail

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http://serverfault.com – Several of our new Exchange servers are failing to relay messages because it is communicating over IPv6 and not matching any receive connector I previously set up. I'm not sure how we are using IP6 since we only have a IPv4 network and we are routing across subnets. I discovered this by typing helo in from the source to the server that is confused by my IP6 address. I saw the IPv6 message and the custom message I gave this receive connector. (connectors with more permission have a different helo) 220 HUB01 client helo asdf 250 HUB01.nfp.com Hello [fe80::cd8:6087:7b1e:99d4%11] More info a ()