Nathaniel Borenstein writes:
As far as I can tell, the only problem that we don't have a handle on at
all so far is non-ascii header data. (The people who think they have a
handle on it tend, I think, to underestimate the risks of messing with
crucial header fields like "From".)
...
3. The new "Real-XXX" headers have NO delivery semantics. Indeed,
A. Nobody (I hope) is suggesting _any_ change to the rfc822 rules
for how headers are constructed as sequences of octets. What is
felt to be required is new rules for how these are displayed as
glyphs [new rules to apply when there are Content headers].
B. If we don't let the Icelanders put their funny glyphs in the Subject
lines and other similar places in the headers then they will go off
and ignore us. Ditto just about everybody. So I don't think you
can say it is unimportant. Nor do I think the Real headers will
be regarded as satisfactory.
C. Stuff in the headers has _NO_ immediate delivery implications.
It is true that the From (/Reply-to/etc) header is used by mail
agents to generate return envelope addresses but I fail to see
anything in the proposals that have been made in this area which
should have any negative impact on this.
If there is a problem I'd really like to understand it. Can we please
have more details of that nightmare that woke you up at 4am :-).
Bob Smart