Message 224896 - Python tracker

> It /does/ break backwards compatibility, but it seems that previous
> logic was incorrect (based on my upcoming checking for consistency
> between RFCs). As such, I'm not sure that it should be fixed < 3.5.
> Thoughts?

Actually, the logic seems to be correct according to RFC 1808 (which the variable names in the tests seem to hint at, as well). I think it's fine to upgrade the semantics to newer RFCs, but we should only do it in 3.5 indeed.