On 08/19/2013 06:24 PM, Marcio Merlone wrote:
Greetings,
I run a mail server for my company with Ubuntu 10.04 LTS and postfix
2.7.0-1ubuntu0.2 and all my users use Thunderbird ESR. We have a
customer running Symantec Messaging Gateway and it converts
attachments of our messages with *special chars* to
"randombogusfilename.dat" (_not_ winmail.dat!). Their support directed
me to this Symantec KB which, in short, says "it's not our fault",
even though they are the only destination where I have noticed this:
http://www.symantec.com/business/support/index?page=content&id=TECH192394
That is a truly horrible "support" article.
It provides no proof, no examples, and no clients that are known to
exhibit this behaviour (as they claim).
Has anyone experienced this or know what's this about and how to
fix/workaround this? Searched Google but no luck.
It's about MIME, which is covered by a set of 6 wordy RFCs:
http://en.wikipedia.org/wiki/MIME
I have seen this before, and while it is usually caused by a client
using a multipart construction that the recipient can't handle - or that
is not 7-bit transfer-safe - the above "support" page doesn't even hint
at what might be the problem.
The specific instance in my case was a vendor implementing the php
mail() system call by appending CRLF manually to all headers. The mail()
documentation clearly states that all lines should end with a bare LF
only, and the effect of this was to break out some inline MIME
multiparts as attachments, and to entirely disappear others.
If you're paying for Symantec support, by all means open a trouble
ticket and force some cooperation for your dollars.
A good start would be full message decodes on both sides (the raw
message both on the client and in the mailbox), as well as packet dumps
on both ends, to see how the message was altered in transit (if it was.)
A tcpdump comparison between the client-side and the mailbox-side would
show if Symantec is correct in that their
mail-gateway-software-money-making-machine does not alter the message in
transit, or if it does.
--
J.
