In <3DD25BF0(_dot_)4050403(_at_)att(_dot_)com> Tony Hansen
<tony(_at_)att(_dot_)com> writes:
RFC 2822 Sections 2.2.1 and 2.2.3 clearly say that all unstructure
headers, including Subject headers, can be folded and unfolded, and how
to do so.
No, it does not say that.
It says that a syntactically correct Internet Message can contain headers
folded according to certain rules, and that the semantic meaning of any
such header is the same as the semantic meaning of that header when fully
unfolded.
It does not anywhere say that Agents may (or may not for that matter)
change the folding for arbitrary reason either en route or on display.
That is because RFC 2822 is completely silent upon what any Agent is
required to do (beyond accepting and transmitting well-formed messages).
That is because it is not the function of RFC 2822 to specify requirements
placed on Agents, that being left to other documents (notably RFC 2821).
So in fact there is nothing said anywhere about when or whether refolding
is permitted, which is perhaps unfortunate since everybody then feels that
they can do whatever they like. I would accept that it is fine for User
Agents to do whatever they think best when displaying messages, but I
think it is disastrous for anything else in the system to be changing
anything (except maybe CTE - and even that leads to assorted woes).
--
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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