At 13:17 -0500 on 02/28/2012, Tony Hansen wrote about Re: "proper"
handling of BCC:
I actually started writing such a doc about a year ago, but never finished it.
Is it worth dusting off?
On 2/28/2012 12:24 PM, Dave Crocker wrote:
On 2/28/2012 9:11 AM, Paul Smith wrote:
OK, I was wrong - but I've never seen a BCC handled in that way
before... I've sometimes received messages with a 'BCC' field
containing addresses who were NOT me (ie I shouldn't have known
they existed), and most MUAs I've seen (in fact, all those I've
investigated fully) just list those recipients in the envelope for
a single copy of the message. So, I've never seen a BCC field in a
message header, used 'correctly'.
We have never really standardized BCC as an end-to-end construct,
at the MUA-MUA level.
Ways it can be handled is for the MUA to submit the BCC header to the
MSA and have it remove the header while cloning the message to create
one master and one copy for each BCC listing only the Address, have
the MSA scan the To and CC assuming that any RCPT-TOs not there are
BCCs and do the cloning, OR add a BCC indicator to the RCPT-TO and do
the cloning. Not that the first 2 alter the MSA while the last alters
both the MSA and MUA.
In any case there needs to be some way of indicating the BCC
contents. Note that there needs to be a way of triggering the
insertion/display of the BCC listing only the recipient in the
recipient's copy of the message that WILL NOT get triggered by a
normal Mailing List message. Options 1 and 3 above qualify since
there is a indication to the MSA to clone the message with a BCC.
Option 2 since it triggers via a mismatch between the To/CC contents
and that of the RECPT-TO will be the problem since there would be no
difference to the MSA between a BCC and a Mailing List generated
Note that I am just winging it and may be missing something and I am
just doing some design spec thoughts above.