Ned,
You asserted that a UA which supports both ssl and protected mail
is interesting to application system design.
Is it possible to describe a general mechanism whereby an originator can
exploit the properties of MOSS and such a UA to *require* that a conformant
UA processes an incoming mail in any particular way?
For example, can one construct a MOSS-protected message such that prior to
decryption, the UA *must* succesfully perform an ftp session and retrieve
some data item, say?
How would one configure such an arrangement, if it is possible?