I therefore wonder if this isn't something we ought to consider
"relaxing" in 2821bis.
If BATV really works everywhere let's do this in 2821ter, please.
I consider 2821bis as "frozen" modulo some DISCUSSes. A general
local part tag syntax with a tag registry should not be limited
to the BATV purposes, it should be open for other applications,
EAI, SRS, SES, whatever.
And who knows, maybe even standardized subaddressing. OK, I can dream, can't I?
In any case, Frank and I are in total agreement here. We really owe it to
ourselves to get general local part structuring right the first time we put
it in place.
The SASL RFCs also offer one or two
very simple mechanisms, and some rules to register more complex
stuff in separate RFCs. Obviously following the MIME model...
One of MIME's best characteristics IMNSHO.