Warwick,
Well and informatively stated -- thanks. I'd also like to endorse
the idea of proceeding with the evolving X.509 definition as one of
the central means for representing keys as PEM and PEM-MIME move
forward; moreover, the recent flurry of activity on this list suggests
that several such activities are moving forward, a Good Thing. I've
been concerned that the premise "The RFC-1422 hierarchy hasn't been
widely deployed" was motivating an unnecessary perception that "We
should drop anything to do with X.509 and instead reinvent the wheel",
and wasn't looking forward to a next phase of discussion about how
to reconstruct a distinguished certificate encoding convention using
MIME structures.
--jl