I gave up trying to fix mutt.  I'ld have to change the structure of its parsing to make
it parse correctly, too much work.  From the comments, they know its screwed up.

I was wrong about what it was misparsing.  The problem was that we returned flags in
a seperate fetch reply.  Fine by the RFC but not fine with mutt.  I just changed
our behaviour because it was a lot easier to do.

Fixes on sources.