How to reproduce:

1. Have an IPv6 network set (easiest way is to have Mac 10.11 and follow this - https://developer.apple.com/library/mac/documentation/NetworkingInternetWeb/Conceptual/NetworkingOverview/UnderstandingandPreparingfortheIPv6Transition/UnderstandingandPreparingfortheIPv6Transition.html#//apple_ref/doc/uid/TP40010220-CH213-SW16 )
2. Have a device connected to it
3. Build and run the attached project on android device
4. Sample contains two GUI buttons: "Check" (based on System.Net.HttpWebRequest) and "Download" (based on UnityEngine.WWW)

Actual result: If button "Check" is pressed on android device connected to IPv6 network, then exception would be logged
Expected result: application on android device connected to IPv6 network works the same as on IPv4 network

Reproducible: 4.7.2f1