Mike Cardwell wrote:
On 10/02/2010 00:04, Ted Mittelstaedt wrote:
Thunderbird only displays the SECOND subject line.
So Thunderbird displays the last Subject line header it comes across. Is
that incorrect behaviour for an MUA?
I think it is. Setting aside the question of whether they are supposed
to be there or not, the purpose of an MUA is to make it easier for
the user to interact with a mail message. Multiple Subject: lines
can contain multiple amounts of information, and only displaying the
last Subject line is denying the user information that they are
supposed to be able to see see.
A deeper question is do all parts of t-bird treat this equally. If
the filtering in t-bird reacts to both Subject line contents then
this definitely is a bug. A user might have a filter saying
"delete all mail with viagrera in its subject line except mail
that has "fred" in it's subject line. The spammer sends a message
with the first subject line having viagrera in it, the second
subject line having fred in it, and the message is not deleted - but
the display only shows viagrea.
You could probably have tested that yourself in the time it took you to
write that paragraph.
Yes but since this is a spamassassin mailing list, I doubt most
users would be interested in a long discussion of problems with
t-bird.
If your a t-bird user who cares, you will investigate it. I don't,
frankly. Once I saw that SA was producing the double "Subject: " line
entries then it seems to me that further discussion on t-bird's
behavior is not warranted, epically on this mailing list.
Is it valid for an email to have
more than one Subject line?
I do not think this defined anywhere. But I won't swear to it. I
think it's not particularly valid, however because the results are
undefined.
Did you check? I would bet that it is defined...
I just took a quick gander at rfc2822 and it states:
"No multiple occurrences of fields (except resent and received).*"
There might be other RFCs involved, but it looks to me from that as
though it's only valid for an email to have one Subject header. It's
understandable that an MUA might not display an invalidly formatted
email correctly.
I'll repeat, it seems to me that further discussion on t-bird's
behavior is not warranted, epically on this mailing list.
Bring it up with Mozilla.
Since this is a SA bug I think I will file it with Mozilla just
to have it in the database, but I would only argue for internal
consistency in t-bird.
You've no reason to believe there is any internal inconsistency with
regards to how Thunderbird treats Subject lines. And if it's true that
it's not valid for an email to have more than one Subject line then this
is not a Thunderbird bug, but still something that they may or may not
wish to workaround.
I'll repeat, it seems to me that further discussion on t-bird's
behavior is not warranted, epically on this mailing list.
Seriously! I know it's a fun diversion, but lets get back to the
real issue.
At this point I am up against a wall. For starters this is an old ver
of sa, old sendmail, etc. This server is scheduled for re-gen soon and
there's no point in filing a bug on the old code. I will continue to
observe and once the server is re-gened then if it keeps happening then
I'll look into it further. I'll probably have to run the server for a
few hours with SA turned off to get the raw spam, not something that is
going to be very popular.
Alternatively, configure your MTA to deliver an unmodified second copy
of all incoming email to a separate maildir.
Yup.
Ted
