And, if all the related party has negotiated well in advance, we might
be able to interoperate.
That's ISO's way of the interoperation.
If you are complaining that we don't have a 0-255 transparent end-to-end
mail transport, well, I agree with you. I wish we had one of these also.
But we currently don't have one.
But MIME is a message format. It is not a mail transport. It does not
make any transport related guarantees because that is outside of its
scope.
I think we need a mail transport that guarantees 0-255 end-to-end
transparency. But the fact that we don't have one yet is not due
to any fault in the MIME spec.
Keith