It's true that this is a backward compatibility problem
in that STARTTLS as currently defined doesn't actually contain
the domain name. As I indicated before, I consider this to
be a design error. There wouldn't have been a compatibility
problem if the domain name had been included in STARTTLS from
the beginning.
Not clear. SMTP can relay a single copy of a message to multiple
recipients at multiple domains. Your suggestion would force a
separate TLS session, or a separate SMTP session, for every distinct
recipient domain.
Keith
--
"Of course the people don't want war. But ... it is always a simple
matter to drag the people along. All you have to do is tell them they
are being attacked, and denounce the pacifists for lack of patriotism
and exposing the country to danger... It works the same way in any
country."
- Hermann Goering, 1947.