[9fans] Unescaped "From" in mail items

[Adrian Tritschler <ajft@ajft.org>]

I've just been archiving a bunch of old email that was sitting in IMAP
folders on a unix system somewhere into local folders on a plan9 system.
I used acme mail to access the remote IMAP folder then save the items I
wanted to local folders.

Some of these have an unescaped "^From" in the text, which seems to have
caused problems when I've saved them to the local mail folders.

The culprits seem to be multipart MIME, similar to:

  From News@InsideApple.Apple.com Tue Jun 19 12:14:30 EST 2007
  Return-Path: ...
  Content-Type: multipart/alternative;
	boundary="----=_Part_6716595_5283499.1182218824922"

  ------=_Part_6716595_5283499.1182218824922
  Content-Type: text/plain; charset=ISO-8859-1
  Content-Transfer-Encoding: quoted-printable
  Content-Disposition: inline

  Blah blah blah
  From $349
  ...
  ------=_Part_6716595_5283499.1182218824922
  Content-Type: text/html; charset=ISO-8859-1
  Content-Transfer-Encoding: quoted-printable
  Content-Disposition: inline
  ...misc HTML...
  ------=_Part_6716595_5283499.1182218824922--

Acme mail now reports multiple messages in the destination folders such
as:

111/	$199
110/	$349
109/	Apple <News@InsideApple.Apple.com>	Tue 19 Jun 2007
	iPod Gift Wrapping is now available.

upas/nedmail reports that the folder has 0 items in it, Acme mail that
it has 136 items.

Were the messages on the original server invalid before I started, is
acme mail handling them incorrectly when saving, or does upas/fs not
interpret them correctly after they've been saved locally?

     Adrian