Mulberry, internationalized addresses, and the future

Hi.

I'm afraid I need to ask the question I've been dreading asking.
During the several years since Mulberry was last actively
maintained and developed, a number of new features have been
introduced into email generally and IMAP in particular.  So far,
I've discovered that the pain of living without them is far less
than contemplating switching email clients -- at least for my
purposes, Mulberry continues to be the best MUA out there by a
rather wide margin.

However, the IETF completed work a few months ago on SMTP and
mail header extensions that permit address local parts that
contain non-ASCII characters, header field data in UTF-8 without
the use of encoded words, and DSNs to match (RFCs 6530 through
6533).  The related documents specifying IMAP (and POP) changes
to accommodate the message header changes will probably go into
IETF Last Call within the next few weeks.  I suspect those of us
with lots of international correspondence are going to find
support for those features essential -- not necessarily
immediately, but within the next year or two.

So the obvious question is: are the various development efforts
likely to produce a Mulberry version (including, for me at
least, a Windows 7/8-compatible one) that incorporates at least
those i18n extensions (some of the newer IMAP stuff would
obviously be good too) in the relatively near future or is this
effectively the end of the line?   And, if the latter, what are
others planning to do?

    john