Updating RFC 5890-5893 (IDNA 2008) to Full Standard
sanz at denic.de
Mon Nov 12 08:13:05 CET 2012
> Even in the notorious Eszett case,
> lower-case Eszett was an undefined code point in IDNA2003.
> IDNA2008 requires that a label containing it be mapped to an
> A-label and looked up. Because of its "look up almost anything"
> rule, an IDNA2003 implementation must map it to an A-label and
> look it up -- exactly the same treatment. An IDNA2003
> implementation that maps it to "ss" is simply non-conforming
> since Stringprep doesn't contain a mapping for the character.
sorry, but that's FUD.
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