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Posted to users@spamassassin.apache.org by mouss <mo...@ml.netoyen.net> on 2009/06/14 13:20:21 UTC
List headers and footers [Re: Unsubscribe]
David Gibbs a écrit :
> LuKreme wrote:
>> The unsubscribe link is right there in plain sight. Whether Gmail
>> conceals it from you has nothing to do with it.
>
> Few consumer mail clients (Gmail, Yahoo, Thunderbird, OE, Outlook, Lotus/Domino, etc) show the user headers by default. This means they are clearly NOT in plain sight.
>
>> No. this is a bad idea. If you can't figure out how to look at mail
>> headers, then you have no business on this list.
>
> The point is, you shouldn't HAVE to look at the mail headers.
>
> Putting the unsubscribe info in the footer is a good idea no mater what.
I am not as convinced as you:
- this modifies the body, thus breaking signatures. when mail gets back
to the same domain (sender and final recipient in same domain), this may
cause problems. I agree that many lists do break signatures so the
receiving site should cope with this, but I am not sure they really do.
- the code is not trivial because of the MIME structure.
- because of the points above and may be other issues, consensus is hard
to reach.
> This is what I do for all the lists I run. Yes, some people are too dumb to read that far ... but MOST people aren't.
>
those who send these "unsubscribe" posts do not really look at the list
messages when they do.
I am convinced that an "unsubscribe" option should be implemented in MUAs.
> david
>
>
Re: List headers and footers [Re: Unsubscribe]
Posted by SM <sm...@resistor.net>.
At 05:08 16-06-2009, McDonald, Dan wrote:
>Altering message bodies might break gpg|pgp signatures, but not DKIM.
It generally invalidates the DKIM signature.
This mailing list does not use Mailman.
Regards,
-sm
Re: List headers and footers [Re: Unsubscribe]
Posted by Jonas Eckerman <jo...@frukt.org>.
McDonald, Dan wrote:
> List servers like mailman resend the message with a different envelope
> header.
Wich doesn't invalidate a DKIM, PGP or S/MIME signature.
> The MTA receiving this message looks for policy statements about
> spamassassin.apache.org, not for policy statements from fantomas.sk.
For SPF yes. For DKIM it should look for policy statements from
"fantomas.sk" since that is the domain of the address used in the From
header.
If the message had contained a DKIM signature, it should of course look
for a DKIM key for the domain specified in the DKIM-Signature header.
Regards
/Jonas
--
Jonas Eckerman
Fruktträdet & Förbundet Sveriges Dövblinda
http://www.fsdb.org/
http://www.frukt.org/
http://whatever.frukt.org/
Re: List headers and footers [Re: Unsubscribe]
Posted by "McDonald, Dan" <Da...@austinenergy.com>.
On Tue, 2009-06-16 at 13:44 +0200, Matus UHLAR - fantomas wrote:
> > On Mon, 15 Jun 2009 09:29:13 +0200
> > Matus UHLAR - fantomas <uh...@fantomas.sk> wrote:
> On 15.06.09 12:30, RW wrote:
> > Would you care to elaborate? You comment makes no sense to me.
>
> the more people use DKIM/PGP, the less unsubscribe-signatures will be
> attached to list mail. And since (I guess) we do want people use such
> techniques, we shouldn't rely on the fact enough people won't use them so
> the "accidental(1)" subscribers won't see them and will complain
>
List servers like mailman resend the message with a different envelope
header. For example, the message I'm quoting was received as:
Jun 16 06:45:23 sa amavis[27515]: (27515-18) Passed CLEAN, [140.211.11.3] [195.168.3.66] <us...@spamassassin.apache.org> -> <Da...@austinenergy.com>, Message-ID: <20...@fantomas.sk>, mail_id: i+AbqzQlLrXO, Hits: -4.291, size: 4375, queued_as: AD64C187, 1077 ms
The MTA receiving this message looks for policy statements about
spamassassin.apache.org, not for policy statements from fantomas.sk. If
spamassassin.apache.org were to alter the body and DKIM sign the
message, it would be fine because it would match
spamassassin.apache.org's policy.
Altering message bodies might break gpg|pgp signatures, but not DKIM.
--
Daniel J McDonald, CCIE # 2495, CISSP # 78281, CNX
www.austinenergy.com
Re: List headers and footers [Re: Unsubscribe]
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> On Mon, 15 Jun 2009 09:29:13 +0200
> Matus UHLAR - fantomas <uh...@fantomas.sk> wrote:
>
> > > On Sun, 14 Jun 2009 13:20:21 +0200
> > > mouss <mo...@ml.netoyen.net> wrote:
> > > > I am not as convinced as you:
> > > >
> > > > - this modifies the body, thus breaking signatures. when mail gets
> > > > back to the same domain (sender and final recipient in same
> > > > domain), this may cause problems. I agree that many lists do
> > > > break signatures so the receiving site should cope with this, but
> > > > I am not sure they really do.
> >
> > On 15.06.09 00:03, RW wrote:
> > > Some lists only add the footer to single part text/plain emails.
> > > Most people don't sign mailing list messages anyway.
> >
> > this makes adding unsubscribe footer somehow useless :)
On 15.06.09 12:30, RW wrote:
> Would you care to elaborate? You comment makes no sense to me.
the more people use DKIM/PGP, the less unsubscribe-signatures will be
attached to list mail. And since (I guess) we do want people use such
techniques, we shouldn't rely on the fact enough people won't use them so
the "accidental(1)" subscribers won't see them and will complain
(1) "accidental" subscriber is a person who asks for subscribing and remembers
to confirm, but forgets the whole stuff in the short time and starts
whining and complaining just after... I have seen them in more mailing
lists.
--
Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
WinError #99999: Out of error messages.
Re: List headers and footers [Re: Unsubscribe]
Posted by RW <rw...@googlemail.com>.
On Mon, 15 Jun 2009 09:29:13 +0200
Matus UHLAR - fantomas <uh...@fantomas.sk> wrote:
> > On Sun, 14 Jun 2009 13:20:21 +0200
> > mouss <mo...@ml.netoyen.net> wrote:
> > > I am not as convinced as you:
> > >
> > > - this modifies the body, thus breaking signatures. when mail gets
> > > back to the same domain (sender and final recipient in same
> > > domain), this may cause problems. I agree that many lists do
> > > break signatures so the receiving site should cope with this, but
> > > I am not sure they really do.
>
> On 15.06.09 00:03, RW wrote:
> > Some lists only add the footer to single part text/plain emails.
> > Most people don't sign mailing list messages anyway.
>
> this makes adding unsubscribe footer somehow useless :)
Would you care to elaborate? You comment makes no sense to me.
Re: List headers and footers [Re: Unsubscribe]
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> On Sun, 14 Jun 2009 13:20:21 +0200
> mouss <mo...@ml.netoyen.net> wrote:
> > I am not as convinced as you:
> >
> > - this modifies the body, thus breaking signatures. when mail gets
> > back to the same domain (sender and final recipient in same domain),
> > this may cause problems. I agree that many lists do break signatures
> > so the receiving site should cope with this, but I am not sure they
> > really do.
On 15.06.09 00:03, RW wrote:
> Some lists only add the footer to single part text/plain emails. Most
> people don't sign mailing list messages anyway.
this makes adding unsubscribe footer somehow useless :)
--
Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
Linux - It's now safe to turn on your computer.
Linux - Teraz mozete pocitac bez obav zapnut.
Re: List headers and footers [Re: Unsubscribe]
Posted by mouss <mo...@ml.netoyen.net>.
RW a écrit :
> On Sun, 14 Jun 2009 13:20:21 +0200
> mouss <mo...@ml.netoyen.net> wrote:
>
>
>> I am not as convinced as you:
>>
>> - this modifies the body, thus breaking signatures. when mail gets
>> back to the same domain (sender and final recipient in same domain),
>> this may cause problems. I agree that many lists do break signatures
>> so the receiving site should cope with this, but I am not sure they
>> really do.
>
> Some lists only add the footer to single part text/plain emails.
given that the most widely used MUAs show the html part, this means such
footers are useless because only few people see them, and these people
can see headers.
(and anyway, whatever part you alter, the sig is broken).
> Most
> people don't sign mailing list messages anyway.
"Most people" have no way to chose which mail to dkim-sign, since this
is done at MTA level. are you confusing this pgp?
Re: List headers and footers [Re: Unsubscribe]
Posted by RW <rw...@googlemail.com>.
On Sun, 14 Jun 2009 13:20:21 +0200
mouss <mo...@ml.netoyen.net> wrote:
> I am not as convinced as you:
>
> - this modifies the body, thus breaking signatures. when mail gets
> back to the same domain (sender and final recipient in same domain),
> this may cause problems. I agree that many lists do break signatures
> so the receiving site should cope with this, but I am not sure they
> really do.
Some lists only add the footer to single part text/plain emails. Most
people don't sign mailing list messages anyway.
Re: List headers and footers [Re: Unsubscribe]
Posted by Matus UHLAR - fantomas <uh...@fantomas.sk>.
> > On Jun 14, 2009, at 8:10 PM, Bill Landry wrote:
> >> If that happens then the message is no longer signed by the original
> >> sender, but rather by the mailing list. Probably not a big deal for a
> >> mailing list, but would be in any person-to-person communications.
> Chris Owen wrote:
> > Why would someone wanting person-to-person communications send mail
> > through Mailman?
On 14.06.09 18:22, Bill Landry wrote:
> [replying back to the list for the benefit of others following this thread]
Thank you. Would be nice if Chris sent the post to list...
> They wouldn't. I was simply trying to illustrate a point that removing
> and resigning a message on a mailing list probably is not a big deal.
I think it is sometimes very good to know that the mail sent to the list was
really sent by the person in From: address.
--
Matus UHLAR - fantomas, uhlar@fantomas.sk ; http://www.fantomas.sk/
Warning: I wish NOT to receive e-mail advertising to this address.
Varovanie: na tuto adresu chcem NEDOSTAVAT akukolvek reklamnu postu.
We are but packets in the Internet of life (userfriendly.org)
Re: List headers and footers [Re: Unsubscribe]
Posted by Jonas Eckerman <jo...@frukt.org>.
David Gibbs wrote:
> Since Mailman adds it's own headers to the messages it processes, any existing signatures in the message are invalidated.
But... They aren't. Some may be, but not all. As an example, the post
from mouss wich you replied to was verified with DKIM by our MX to be
signedhave passed through a system correctly signing for
"mouss@ml.netoyen.net".
DKIM specifies wich headers it includes in the signature, and ignores
headers that are prepended after the signature. As long as mailman
leaves the specified headers below the signature alone, adding it's own
headers won't invalidate DKIM signatures.
Also, some signatures simply don't care about the *message* headers at
all, only about the body or the signed MIME part(s).
> Thus, Mailman has to remove any existing signatures and let the MTA resign the message after it's been processed.
If mailman has been set up to change the body (adding a footer for
example) or change headers that can reasonably be expected to appear in
signatures (like From or Subject for example), it should remove certain
signatures (like DKIM) and (preferably) replace them with the
authentication results at the current point (of course, it should (when
applicable) include any prepended results header(s) in it's own
signature if it then resigns the message).
Otherwise I see no reason for it to remove signatures. Wich is an
obvious reason *not* to add a footer or a subject tag, as well as a
reason not to rewrite From and reply-To. Wether or not that reason is
important is a personal opinion, but it is valid.
If signatures are left in places and important data isn't changed, our
regular verification methods can verify wether a post purporting to be
mouss (for example) came from a system that should send mail from mouss.
If mailman removes existing signatures or changes important data, we can
not verify that the mail really was sent though a system supposed to
send mail from mouss.
If mailman (or it's MTA) adds authentication results, we have to trust
the system (and it's administator(s)) in order to be reasonably sure
wether the mail was sent from an autorized system or not. This may not
be reasonable for all list hosts.
Note: Important data for the mail from mouss that you replied to is the
body, and the following headers:
Date:From:Reply-To:MIME-Version:To:Subject:References:In-Reply-To:Content-Type:Content-Transfer-Encoding;
As long as mailman (or anything else) doesn't change that data, the DKIM
signature will still be valid and verifiable, wich it is here.
Regards
/Jonas
--
Jonas Eckerman
Fruktträdet & Förbundet Sveriges Dövblinda
http://www.fsdb.org/
http://www.frukt.org/
http://whatever.frukt.org/
Re: List headers and footers [Re: Unsubscribe]
Posted by Bill Landry <bi...@inetmsg.com>.
> mouss wrote:
>>> Mailman has specific functionality to remove signature headers so
>>> that the message can be resigned as it's sent out.
>>
>> which doesn't help, because if I get mail claiming to come "From:
>> <mo...@netoyen.net>", yet it doesn't have a sig of mine, I don't
>> really care if some fancy mailman owner has added his own.
>
> Huh? I really don't understand what you just wrote.
>
> "Mailman" is a mailing list management program (which is used to manage
> this list, fwiw). And the signatures I was talking about are DKIM or
> Domainkeys.
>
> Since Mailman adds it's own headers to the messages it processes, any
> existing signatures in the message are invalidated. Thus, Mailman has to
> remove any existing signatures and let the MTA resign the message after
> it's been processed.
This is *not* correct. Check the headers of this message and check the SA
test results. The list server added its headers, did not strip my DK &
DKIM signatures, and SA shows that the message contains DK & DKIM
signatures and that they are still valid.
Headers added after signing do *not* cause a problem if they are added in
the proper order, above the ones used for signing, as is the standard.
Bill
Re: List headers and footers [Re: Unsubscribe]
Posted by Benny Pedersen <me...@junc.org>.
On Tirs, Juni 16, 2009 03:13, David Gibbs wrote:
> Since Mailman adds it's own headers to the messages it processes, any
> existing signatures in the message are invalidated. Thus, Mailman has to
> remove any existing signatures and let the MTA resign the message after
> it's been processed.
i am on more maillists where this is not so, even my own mailman setup
does not have a problem with dkim signing, eg on postfix maillist my
header is not invalid after i get my mails back from there maillist
on another list i have problem since that there site using clamsmtp that
breaks dkim (fix is to disable add heder in clamsmtp)
> Or are you just being sarcastic?
just on facebook :)
--
xpoint
Re: List headers and footers [Re: Unsubscribe]
Posted by David Gibbs <da...@midrange.com>.
mouss wrote:
>> Mailman has specific functionality to remove signature headers so
>> that the message can be resigned as it's sent out.
>
> which doesn't help, because if I get mail claiming to come "From:
> <mo...@netoyen.net>", yet it doesn't have a sig of mine, I don't
> really care if some fancy mailman owner has added his own.
Huh? I really don't understand what you just wrote.
"Mailman" is a mailing list management program (which is used to manage this list, fwiw). And the signatures I was talking about are DKIM or Domainkeys.
Since Mailman adds it's own headers to the messages it processes, any existing signatures in the message are invalidated. Thus, Mailman has to remove any existing signatures and let the MTA resign the message after it's been processed.
Or are you just being sarcastic?
david
--
IBM i on Power -- For when you can't afford to be out of business.
Re: List headers and footers [Re: Unsubscribe]
Posted by mouss <mo...@ml.netoyen.net>.
David Gibbs a écrit :
> Bill Landry wrote:
>> This may be true if the sender were adding the footer before signing and
>> sending the message to the list. However, not true if it's the mailing
>> list that is adding the footer after the original sender has already
>> signed the message.
>
> As I understand it, in order for the signatures to be valid, the message has to be signed by the sender ... because most mailing list software adds headers.
>
> Mailman has specific functionality to remove signature headers so that the message can be resigned as it's sent out.
>
which doesn't help, because if I get mail claiming to come "From:
<mo...@netoyen.net>", yet it doesn't have a sig of mine, I don't really
care if some fancy mailman owner has added his own.
if all it takes is to claim to be a "mailman", then I can fake all
signatures of the whole internet by adding mailman headers.
Re: List headers and footers [Re: Unsubscribe]
Posted by Bill Landry <bi...@inetmsg.com>.
Chris Owen wrote:
> On Jun 14, 2009, at 8:10 PM, Bill Landry wrote:
>
>>> Mailman has specific functionality to remove signature headers so
>>> that the message can be resigned as it's sent out.
>
>> If that happens then the message is no longer signed by the original
>> sender, but rather by the mailing list. Probably not a big deal for a
>> mailing list, but would be in any person-to-person communications.
>
>
> Why would someone wanting person-to-person communications send mail
> through Mailman?
[replying back to the list for the benefit of others following this thread]
They wouldn't. I was simply trying to illustrate a point that removing
and resigning a message on a mailing list probably is not a big deal.
But if, for example, a receiving MTA were to add some kind of footer to
a signed message in a person-to-person communication (not a mailing list
communication), then that would effectively render the DK and/or DKIM
signatures invalid, as the message content would have changed.
The same is true if a mailing list adds a footer to a message and does
not remove the original DK and DKIM signatures, as the list recipients
would receive the message with invalid signatures, and SA would report
them as invalid.
Bill
Re: List headers and footers [Re: Unsubscribe]
Posted by Bill Landry <bi...@inetmsg.com>.
David Gibbs wrote:
> Bill Landry wrote:
>> This may be true if the sender were adding the footer before signing and
>> sending the message to the list. However, not true if it's the mailing
>> list that is adding the footer after the original sender has already
>> signed the message.
>
> As I understand it, in order for the signatures to be valid, the message has to be signed by the sender ... because most mailing list software adds headers.
As long as the headers are added in the proper order, they will not
break DK & DKIM signing. But adding anything to the body will break the
signatures, as the body is included as part of the signature.
If you take a look at the headers of this message, you will see what
headers I've included in my DK & DKIM signatures, as well as the message
body. Any changes in any of these areas will render the signature invalid.
> Mailman has specific functionality to remove signature headers so that the message can be resigned as it's sent out.
If that happens then the message is no longer signed by the original
sender, but rather by the mailing list. Probably not a big deal for a
mailing list, but would be in any person-to-person communications.
Bill
Re: List headers and footers [Re: Unsubscribe]
Posted by David Gibbs <da...@midrange.com>.
Bill Landry wrote:
> This may be true if the sender were adding the footer before signing and
> sending the message to the list. However, not true if it's the mailing
> list that is adding the footer after the original sender has already
> signed the message.
As I understand it, in order for the signatures to be valid, the message has to be signed by the sender ... because most mailing list software adds headers.
Mailman has specific functionality to remove signature headers so that the message can be resigned as it's sent out.
david
--
IBM i on Power -- For when you can't afford to be out of business.
Re: List headers and footers [Re: Unsubscribe]
Posted by Bill Landry <bi...@inetmsg.com>.
David Gibbs wrote:
> mouss wrote:
>> - mail admin at example.com configures his mail system to sign all
>> outbound mail with DKIM
>> - he rejects any mail with a From: in his domain if it doesn't have a
>> valid DKIM signature
>> - joe@example.com posts to a list that appends a footer (or munges the
>> Reply-To header, assuming this is used in the signature).
>> - list resends the message to mx.example.com.
>> - mail is From: joe@example.com, but it is either not signed (list
>> removed the signature) or the sig is not valid (message altered by list).
>
> I don't think DKIM / Domainkeys will be invalidated by adding a footer ... as the footer is added to the message before it is signed and resent.
This may be true if the sender were adding the footer before signing and
sending the message to the list. However, not true if it's the mailing
list that is adding the footer after the original sender has already
signed the message.
Bill
Re: List headers and footers [Re: Unsubscribe]
Posted by David Gibbs <da...@midrange.com>.
mouss wrote:
> - mail admin at example.com configures his mail system to sign all
> outbound mail with DKIM
> - he rejects any mail with a From: in his domain if it doesn't have a
> valid DKIM signature
> - joe@example.com posts to a list that appends a footer (or munges the
> Reply-To header, assuming this is used in the signature).
> - list resends the message to mx.example.com.
> - mail is From: joe@example.com, but it is either not signed (list
> removed the signature) or the sig is not valid (message altered by list).
I don't think DKIM / Domainkeys will be invalidated by adding a footer ... as the footer is added to the message before it is signed and resent.
> BTW, in .fr, most MUAs (including webmail) translate "spam" as "Messages
> undesirables", which most users naturally understand as a way to report
> mail they don't want. so even if you send them mail regularly, but there
> is one they didn't like, they'll hit the "This Is Spam" button. The
> fault is shared between the luser and the UI designer/translater!
Yeah ... but I've also had cases of idiots who were deliberately reporting mailing list messages as spam because they couldn't be bothered to unsubscribe.
david
--
IBM i on Power -- For when you can't afford to be out of business.
Re: List headers and footers [Re: Unsubscribe]
Posted by mouss <mo...@ml.netoyen.net>.
David Gibbs a écrit :
> mouss wrote:
>> - this modifies the body, thus breaking signatures. when mail gets back
>> to the same domain (sender and final recipient in same domain), this may
>> cause problems. I agree that many lists do break signatures so the
>> receiving site should cope with this, but I am not sure they really do.
>
> Signatures ... as in DKIM / DomainKeys? Or GPG signatures?
>
any (cryptographic) signature method that is invalidated if text is
added to the body.
here is an example:
- mail admin at example.com configures his mail system to sign all
outbound mail with DKIM
- he rejects any mail with a From: in his domain if it doesn't have a
valid DKIM signature
- joe@example.com posts to a list that appends a footer (or munges the
Reply-To header, assuming this is used in the signature).
- list resends the message to mx.example.com.
- mail is From: joe@example.com, but it is either not signed (list
removed the signature) or the sig is not valid (message altered by list).
>> - the code is not trivial because of the MIME structure.
>
BTW. dspam once had a bug (dunno if it was fixed): when you enabled the
"signature in body" option, it appended text to the body, which
obviously won't work for html mail for example!
> Ah, this may be the case ... I'm unfamiliar with the exact configuration of the SA lists. On my own list server I convert everything to plain text to avoid problems with incompatible mail clients.
>
yes, that usually works (in "text only" lists such as this one where we
don't exchange images...). but even this is a hard game because you need
to take a decision when the message is broken (incorrect html, ... etc).
this is somewhat similar to the problem of browsers trying to fix
incorrect html, but each browser has its heuristics, and you're never
sure what the browser guessed is what the page author intended!
that said, I agree that in a "text only" list, it should work correctly,
and even if it does not, the fault is in the sender side ;-p
>>> This is what I do for all the lists I run. Yes, some people are too dumb to read that far ... but MOST people aren't.
>>>
>> those who send these "unsubscribe" posts do not really look at the list
>> messages when they do.
>
> True enough. Add to those the people who think the best way to get unsubscribed from a list is to simply report it as spam.
>
BTW, in .fr, most MUAs (including webmail) translate "spam" as "Messages
undesirables", which most users naturally understand as a way to report
mail they don't want. so even if you send them mail regularly, but there
is one they didn't like, they'll hit the "This Is Spam" button. The
fault is shared between the luser and the UI designer/translater!
>> I am convinced that an "unsubscribe" option should be implemented in MUAs.
>
> I completely concur. It's not rocket science.
>
> I *THINK* I saw a tbird add in that implements this kind of functionality, but it would be better as part of the core.
>
yep.
> david
>
Re: List headers and footers [Re: Unsubscribe]
Posted by LuKreme <kr...@kreme.com>.
On 14-Jun-2009, at 10:23, David Gibbs wrote:
> mouss wrote:
>> - this modifies the body, thus breaking signatures. when mail gets
>> back
>> to the same domain (sender and final recipient in same domain),
>> this may
>> cause problems. I agree that many lists do break signatures so the
>> receiving site should cope with this, but I am not sure they really
>> do.
>
> Signatures ... as in DKIM / DomainKeys? Or GPG signatures?
Both.
--
Satan oscillate my metallic sonatas
Re: List headers and footers [Re: Unsubscribe]
Posted by David Gibbs <da...@midrange.com>.
mouss wrote:
> - this modifies the body, thus breaking signatures. when mail gets back
> to the same domain (sender and final recipient in same domain), this may
> cause problems. I agree that many lists do break signatures so the
> receiving site should cope with this, but I am not sure they really do.
Signatures ... as in DKIM / DomainKeys? Or GPG signatures?
> - the code is not trivial because of the MIME structure.
Ah, this may be the case ... I'm unfamiliar with the exact configuration of the SA lists. On my own list server I convert everything to plain text to avoid problems with incompatible mail clients.
>> This is what I do for all the lists I run. Yes, some people are too dumb to read that far ... but MOST people aren't.
>>
>
> those who send these "unsubscribe" posts do not really look at the list
> messages when they do.
True enough. Add to those the people who think the best way to get unsubscribed from a list is to simply report it as spam.
> I am convinced that an "unsubscribe" option should be implemented in MUAs.
I completely concur. It's not rocket science.
I *THINK* I saw a tbird add in that implements this kind of functionality, but it would be better as part of the core.
david
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