Misuse of any protocol feature can cause interoperability problems.
ni8mc> But it is far from clear that the cases where X- field use is causing
interop
ni8mc> problems actually constitute "misuse".
In fact I would say that this is an example of using the "protocol" exactly the
way it
was intended, with an undesired, but entirely predictable, effect.
Alas, sometimes excellent intentions and even good designing/thinking
can produce very bad results. We simply have to acknowledge the outcome
and find a way to fix it.
When we added X-headers, I thought it was a very clever idea, indeed.
Instead it has proved both problematic and aesthetically ugly. (Since
email headers are user-visible, aesthetics matter, at least somewhat.)
My own, primary concern about them is having an "experimental" header
become a defacto standard and then having to find a way to get folks to
use a new, non-X header name for it. I believe that hasn't been
successful yet, or at least not much.
d/
d/
--
Dave Crocker <dcrocker-at-brandenburg-dot-com>
Brandenburg InternetWorking <www.brandenburg.com>
Sunnyvale, CA USA <tel:+1.408.246.8253>