This bug has nothing to do with Courier. I've seen it myself over the past
two years - Qmail to Exchange environment.
The problem is that the *client* is sending a BINARY attachment (PDF) and
it's Q-P'ing it instead of base64'ing it.
I don't know if the client does Q-P incorrectly - but that was the problem.
I found that the resulting PDF couldn't be viewed under *any* Unix mailer
(i.e. the PDF was corrupt), but if it was forwarded through to an Exchange
server, Outlook could read it fine, and if you IMAP'ed into Exchange, a Unix
mailer could now read it (IMAP showed it as base64 BTW).
I'd guess it's something to do with line delimiters and how Winblows does it
with Q-P vs how it should have been done.
Information Security Manager, Trimble Navigation Ltd.
Phone: +64 3 9635 377 Fax: +64 3 9635 417
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