Thomas Roessler <roessler(_at_)does-not-exist(_dot_)org> writes:
I agree with Jon's opinion. PGP/MIME interoperability is bad.
Really? It certainly won't get worse than MIME interoperability in
general.
MIME interop isn't very good, when you beyond the simple features. As
an example, my mail server filter multipart/signed. I have no idea
why, and of course it is a bug, but the point is that for some reason
the deployment of PGP/MIME failed here.
I believe it is the design of RFC 1847 that makes interoperability
low. I'm even considering arguing for the solution chosen by Outlook
PGP plugins when it comes to PGP and MIME, just PGP encrypt each
MIME part without touching the MIME headers at all.
Funny enough, S/MIME uses RFC 1847 as well, and that one works.
S/MIME doesn't use RFC 1847 for encrypting messages, and S/MIME allows
non-RFC 1847 mechanisms when it comes to signed messages as well.