Re: A couple of comments on the open issues...

John C Klensin writes:
> There are no standards at all for interpreting the local part. 

False.

RFC 822 clearly states that the local part consists of ASCII characters.
The ASCII standard specifies interpretations of bytes 33-126 as glyphs.

(If you're under the delusion that this interpretation is not actually
standardized, or that users don't rely on it, please switch your MUA to
EBCDIC header I/O for a month and let us know the results.)

The question of which mailbox names are valid on a system, and how those
mailboxes are handled, is (almost) entirely up to the system. But we
have a global interpretation of ASCII mailbox names as glyphs.

---D. J. Bernstein, Associate Professor, Department of Mathematics,
Statistics, and Computer Science, University of Illinois at Chicago