In
<5(_dot_)1(_dot_)1(_dot_)2(_dot_)2(_dot_)20020506105822(_dot_)02906aa8(_at_)jay(_dot_)songbird(_dot_)com>
Dave Crocker <dcrocker(_at_)brandenburg(_dot_)com> writes:
the theory is that there is benefit in extending this model for other
parametric local-part situations. the clear requirement, however, is
backward compatibility so that the more popular free-form local-part continues.
Well if you want to make it easier to extend the existing headers with new
functionalities, then may I draw your attention to what Usefor is doing.
We have decreed that ALL headers may include MIME-style parameters (i.e.
may be followed by "; foo=value"), where parameters are to be ignored if
not having a recognized meaning.
Actually, we have made little use of this feature for now. It is intended
to allow unheard of extensions in the future. So it is a MUST accept (and
ignore for now) but SHOULD NOT generate (so as not to confuse present
agents). And we took care not to require it in the critical mail headers
like From and Reply-To (where there are slight parsing difficulties
anyway). An investment for the long term future.
--
Charles H. Lindsey ---------At Home, doing my own thing------------------------
Tel: +44 161 436 6131 Fax: +44 161 436 6133 Web: http://www.cs.man.ac.uk/~chl
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