2 Questions:

1) MM_QUIET doesn't seem to work in the 212 version of metamail.

2) I've been pondering how I am going to send you this 40mb mail message.
I was going to split it up using the "parts" mechanism, but then it occurred to me.
My software has no business worrying about message size. Its up to the mail
delivery agent to do that form me. I should be able to compose a very
long message, and pass it off to sendmail (well, a pre-processor to sendmail).
if the message is too long, based upon the src/dst etc, then sendmail should
break it into multiple parts for me, and send it as multiple messages. As the
user (sender) I should be unaware this is happening.

Similarly, on the receiving end, the separate parts should be assembled as they
arrive; I shouldn't have do deal with them at all as multiple messages.

I guess what I am proposing are two utility programs:

msplit <max_lines> <max_bytes>

that takes 1 mail message and splits it into N messages and

mcombine <parts...>
mcombine <partially_assembled_thingy> <parts...>

that any mail system can call to achieve a uniform mechanism of splitting
and recombining messages, Kind of like: