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Which spam filtering package do you think is best?

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loupicciano at comcast

Dec 21, 2010, 8:12 PM

Post #1 of 19 (738 views)
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Which spam filtering package do you think is best?

Can I collect opinions here about favorite/least favorite spam filtering packages, for use in a dbmail environment?

What have you had luck with? What works best? What's your opinion? Which should a happy dbmail (postfix) user, now getting too much spam, use for filtration?

TIA, Lou Picciano

tokul at users

Dec 21, 2010, 9:39 PM

Post #2 of 19 (724 views)
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Re: Which spam filtering package do you think is best? [In reply to]

2010.12.22 06:12 Lou Picciano rašė:
> Can I collect opinions here about favorite/least favorite spam filtering
> packages, for use in a dbmail environment?
>
>
> What have you had luck with? What works best? What's your opinion? Which
> should a happy dbmail (postfix) user, now getting too much spam, use for
> filtration?

The only spam filtering "packages" are commercial ones. You order service
and you get blackbox package which filters spam. Your spam volume goes
down, but you don't have good explanation how and why.

If you want to use some tools for spam filtering, it depends how you want
to filter spam. You familiarize with spam filtering options, learn them
and choose the ones that work for you. Those tools are not packages. They
give you only one or two spam filtering options and in some cases they can
be used together.

* RBL (standard postfix feature, you just have to choose servers carefully)
* Greylisting (postfix-policyd or postgrey)
* Content based filtering (can be implemented in Postfix before dbmail
local delivery agent kicks in)
* Bayes filtering (can be implemented in Postfix before dbmail local
delivery agent kicks in, possible problems with filter training setup)
* TMDA

--
Tomas

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h.reindl at thelounge

Dec 22, 2010, 4:32 AM

Post #3 of 19 (722 views)
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Re: Which spam filtering package do you think is best? [In reply to]

We are using "Barracuda Spam & Virus Firewal" since some years
and changed the hardware-appliance some weeks ago aganist
the "virtual appliance" form vmware

It works great and is easy to use / control
Qurantine for users, domain settings and a nice interface
well not really cheap but implementing the features with
spamassasin and other tools would takes so much more work

http://www.barracudanetworks.com/ns/products/vm_overview.php

Am 22.12.2010 05:12, schrieb Lou Picciano:
> Can I collect opinions here about favorite/least favorite spam filtering packages, for use in a dbmail environment?
>
> What have you had luck with? What works best? What's your opinion? Which should a happy dbmail (postfix) user, now
> getting too much spam, use for filtration?
>
> TIA, Lou Picciano
>
> _______________________________________________
> DBmail mailing list
> DBmail [at] dbmail
> http://mailman.fastxs.nl/cgi-bin/mailman/listinfo/dbmail

--

Mit besten Grüßen, Reindl Harald
the lounge interactive design GmbH
A-1060 Vienna, Hofmühlgasse 17
CTO / software-development / cms-solutions
p: +43 (1) 595 3999 33, m: +43 (676) 40 221 40
icq: 154546673, http://www.thelounge.net/

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gordan at bobich

Dec 22, 2010, 4:36 AM

Post #4 of 19 (722 views)
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Re: Which spam filtering package do you think is best? [In reply to]

Lou Picciano wrote:
> Can I collect opinions here about favorite/least favorite spam filtering
> packages, for use in a dbmail environment?
>
> What have you had luck with? What works best? What's your opinion? Which
> should a happy dbmail (postfix) user, now getting too much spam, use for
> filtration?

I don't use content based spam filtering at all. The three techniques
that I find work really well combined are:

1) nolisting
http://en.wikipedia.org/wiki/Nolisting
I find it works best when you have at least two dummy high priority
decoys before the real MX, and some lower priority ones, too. Spammers
typically go for either the first one or the last one.

2) RBLs. Spamhaus is probably the best option, and it's free until you
need to query it more than about 400,000 times / day. Stay away from UCE
Protect, their policies are wholly unreasonable.

3) Clamav Milter
I don't really consider this to be optional any more. Fairly trivial to
set up, too.

In that order.

I wouldn't bother with content-based filtering - it's expensive and
prone to false positives, especially if you go as far as scanning image
based spam by extracting images and OCR-ing the pictures.

I get about 3-4 spams/week in my inbox. After decoys that protect me
from 75%+ of the spam, my MTA rejection rates on what's left are between
30 and 50% (RBLs, AV milter).

Last year I switched off my anti-spam defences for a test, and the
torrent of spam was quite staggering - about 100-200/day.

Gordan
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larryh at bmvcorp

Dec 22, 2010, 8:16 AM

Post #5 of 19 (719 views)
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Re: Which spam filtering package do you think is best? [In reply to]

I use Mailscanner to manage spamassassin and clamav. You can configure
spamassassin to use RBLs and/or a bayesian filter.

Lou Picciano wrote:
>
> Can I collect opinions here about favorite/least favorite spam filtering
> packages, for use in a dbmail environment?
>
>
> What have you had luck with? What works best? What's your opinion? Which
> should a happy dbmail (postfix) user, now getting too much spam, use for
> filtration?
>
>
> TIA, Lou Picciano
> _______________________________________________
> DBmail mailing list
> DBmail [at] dbmail
> http://mailman.fastxs.nl/cgi-bin/mailman/listinfo/dbmail
>
>

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gordan at bobich

Dec 22, 2010, 8:52 AM

Post #6 of 19 (722 views)
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Re: Which spam filtering package do you think is best? [In reply to]

Larry H. wrote:
> I use Mailscanner to manage spamassassin and clamav. You can configure
> spamassassin to use RBLs and/or a bayesian filter.

What possible reason could there be for using MailScanner and
SpamAssassin if you are only going to filter based on ClamAV and RBLs?
Both are hookable directly into postfix (the OP mentioned postfix). I'd
only bother with either if you really, absolutely need content-based
filtering.

Last I checked, MailScanner was written in Perl and IIRC SpamAssassin in
Python (don't quote me on the latter, I may be wrong). Not really what
you want to run on a heavily loaded mail system. Then again, maybe your
system isn't facing as much load as the ones I've had to work with...

Gordan
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larryh at bmvcorp

Dec 22, 2010, 9:36 AM

Post #7 of 19 (721 views)
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Re: Which spam filtering package do you think is best? [In reply to]

The reason I use Mailscanner is because it can do a lot more that connect
clamav and spamassassin's RBL feature to postfix. It gives you the ability
to blacklist email addresses, block certain filetypes, allow certain
filetypes for certain email addresses and a lot more. My mail server only
supports about 200 clients (Most using POP3) and the load is usually at 0.60
during peak hours.

Gordan Bobic wrote:
>
> Larry H. wrote:
>> I use Mailscanner to manage spamassassin and clamav. You can configure
>> spamassassin to use RBLs and/or a bayesian filter.
>
> What possible reason could there be for using MailScanner and
> SpamAssassin if you are only going to filter based on ClamAV and RBLs?
> Both are hookable directly into postfix (the OP mentioned postfix). I'd
> only bother with either if you really, absolutely need content-based
> filtering.
>
> Last I checked, MailScanner was written in Perl and IIRC SpamAssassin in
> Python (don't quote me on the latter, I may be wrong). Not really what
> you want to run on a heavily loaded mail system. Then again, maybe your
> system isn't facing as much load as the ones I've had to work with...
>
> Gordan
> _______________________________________________
> DBmail mailing list
> DBmail [at] dbmail
> http://mailman.fastxs.nl/cgi-bin/mailman/listinfo/dbmail
>
>

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myzamri at gmail

Dec 30, 2010, 8:07 AM

Post #8 of 19 (684 views)
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Re: Which spam filtering package do you think is best? [In reply to]

On Wed, Dec 22, 2010 at 12:12 PM, Lou Picciano <loupicciano [at] comcast>wrote:

> Can I collect opinions here about favorite/least favorite spam filtering
> packages, for use in a dbmail environment?
>
> What have you had luck with? What works best? What's your opinion? Which
> should a happy dbmail (postfix) user, now getting too much spam, use for
> filtration?
>
> TIA, Lou Picciano
>
> ________

I'm using sqlgrey (postgrey implementation with database (mysql)) and
spamassassin. So far so good. sqlgrey is the best tool (to my knowledge) for
front-line protection against spam before spamassassin takes over the job.
I'm welcome for other suggestions.

gordan at bobich

Dec 30, 2010, 8:15 AM

Post #9 of 19 (686 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

zamri wrote:

> Can I collect opinions here about favorite/least favorite spam
> filtering packages, for use in a dbmail environment?
>
> What have you had luck with? What works best? What's your opinion?
> Which should a happy dbmail (postfix) user, now getting too much
> spam, use for filtration?
>
> TIA, Lou Picciano
>
> I'm using sqlgrey (postgrey implementation with database (mysql)) and
> spamassassin. So far so good. sqlgrey is the best tool (to my knowledge)
> for front-line protection against spam before spamassassin takes over
> the job. I'm welcome for other suggestions.

So, you don't mind not receiving mail from multi-homed hosts (*cough*
gmail *cough*)? Greylistting's very concept is broken by design.

Gordan
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tokul at users

Dec 30, 2010, 9:00 AM

Post #10 of 19 (682 views)
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Re: Which spam filtering package do you think is best? [In reply to]

2010.12.30 18:15 Gordan Bobic rašė:
> zamri wrote:
>
>> Can I collect opinions here about favorite/least favorite spam
>> filtering packages, for use in a dbmail environment?
>>
>> What have you had luck with? What works best? What's your opinion?
>> Which should a happy dbmail (postfix) user, now getting too much
>> spam, use for filtration?
>>
>> TIA, Lou Picciano
>>
>> I'm using sqlgrey (postgrey implementation with database (mysql)) and
>> spamassassin. So far so good. sqlgrey is the best tool (to my knowledge)
>> for front-line protection against spam before spamassassin takes over
>> the job. I'm welcome for other suggestions.
>
> So, you don't mind not receiving mail from multi-homed hosts (*cough*
> gmail *cough*)? Greylistting's very concept is broken by design.

So using myriad of outgoing email servers is not something unusual.

Anyone who does not like some tool can call it broken by design.

--
Tomas

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gordan at bobich

Dec 30, 2010, 9:29 AM

Post #11 of 19 (683 views)
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Re: Which spam filtering package do you think is best? [In reply to]

Tomas Kuliavas wrote:

>>> Can I collect opinions here about favorite/least favorite spam
>>> filtering packages, for use in a dbmail environment?
>>>
>>> What have you had luck with? What works best? What's your opinion?
>>> Which should a happy dbmail (postfix) user, now getting too much
>>> spam, use for filtration?
>>>
>>> TIA, Lou Picciano
>>>
>>> I'm using sqlgrey (postgrey implementation with database (mysql)) and
>>> spamassassin. So far so good. sqlgrey is the best tool (to my knowledge)
>>> for front-line protection against spam before spamassassin takes over
>>> the job. I'm welcome for other suggestions.
>> So, you don't mind not receiving mail from multi-homed hosts (*cough*
>> gmail *cough*)? Greylistting's very concept is broken by design.
>
> So using myriad of outgoing email servers is not something unusual.

You are missing the point. Consider this scenario. A server has multiple
NICs on different networks, all routing to the internet. The default
route gets rotated around (when it expires, after a few minutes) in
order to load balance. This sort of a setup is fairly common on big
installations (helps with resiliency, too).

So, such a server gets a message in it's outbound spool. It tries to
deliver it to you via one of it's several routes/NICs. You see the
connection, greylist it and temporarily reject. Server goes away for a
bit. By the time it retries, the route has expired, and you get an
incoming connection from the same server but from a different source IP.
Your greylist hasn't seen that IP, so you temporarily reject again. This
can go on forever. Some of your mail might get lucky and get through.
Most will probably get massively delayed, and some will likely keep
bouncing in the outgoing spool until it expires and bounces back,
several days later.

> Anyone who does not like some tool can call it broken by design.

You are mixing up cause and effect. I dislike tools if they are broken.
I don't call them broken because I dislike them.

Gordan
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tokul at users

Dec 30, 2010, 9:54 AM

Post #12 of 19 (682 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

2010.12.30 19:29 Gordan Bobic rašė:
> Tomas Kuliavas wrote:
>
>>>> Can I collect opinions here about favorite/least favorite spam
>>>> filtering packages, for use in a dbmail environment?
>>>>
>>>> What have you had luck with? What works best? What's your opinion?
>>>> Which should a happy dbmail (postfix) user, now getting too much
>>>> spam, use for filtration?
>>>>
>>>> TIA, Lou Picciano
>>>>
>>>> I'm using sqlgrey (postgrey implementation with database (mysql)) and
>>>> spamassassin. So far so good. sqlgrey is the best tool (to my
>>>> knowledge)
>>>> for front-line protection against spam before spamassassin takes over
>>>> the job. I'm welcome for other suggestions.
>>> So, you don't mind not receiving mail from multi-homed hosts (*cough*
>>> gmail *cough*)? Greylistting's very concept is broken by design.
>>
>> So using myriad of outgoing email servers is not something unusual.
>
> You are missing the point. Consider this scenario. A server has multiple
> NICs on different networks, all routing to the internet. The default
> route gets rotated around (when it expires, after a few minutes) in
> order to load balance. This sort of a setup is fairly common on big
> installations (helps with resiliency, too).
>
> So, such a server gets a message in it's outbound spool. It tries to
> deliver it to you via one of it's several routes/NICs. You see the
> connection, greylist it and temporarily reject. Server goes away for a
> bit. By the time it retries, the route has expired, and you get an
> incoming connection from the same server but from a different source IP.
> Your greylist hasn't seen that IP, so you temporarily reject again. This
> can go on forever. Some of your mail might get lucky and get through.
> Most will probably get massively delayed, and some will likely keep
> bouncing in the outgoing spool until it expires and bounces back,
> several days later.

So network design with routes that last less than couple of hours is
perfectly ok? Trying to feed same email from different locations is
exactly what spammer would do.

>> Anyone who does not like some tool can call it broken by design.
>
> You are mixing up cause and effect. I dislike tools if they are broken.
> I don't call them broken because I dislike them.

If you have information that tool has problems with some types of
networking setups, you should say that it has problems with such setups.
Tool works fine with other servers. Design is not broken. Calling
something broken by design does not show what is broken in design. It only
shows that you dislike the tool.

--
Tomas

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helpaz at gmail

Dec 30, 2010, 10:29 AM

Post #13 of 19 (683 views)
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Re: Which spam filtering package do you think is best? [In reply to]

On Thu, Dec 30, 2010 at 18:07, zamri <myzamri [at] gmail> wrote:

> I'm using sqlgrey (postgrey implementation with database (mysql)) and
> spamassassin. So far so good. sqlgrey is the best tool (to my knowledge) for
> front-line protection against spam before spamassassin takes over the job.
> I'm welcome for other suggestions.

for postgrey implementation I would recommend policyd (we use v1).
it has such features as whitelisting (by ip, by sender). so you can
whitelist big mail players (gmail, facebook and etc).
blacklisting (by ip, by sender). automatic blacklisting and etc.

but this system also requires monitoring. I have written script which
checks blacklisted hosts and parses maillog to check what senders to
which recipients this host was trying to send mail. only some hosts
got false blacklisted. and after few months it did not got any false
blacklisted hosts. even after few years we got complains about that we
block some hosts, and after check of logs it was clear that those
hosts sends "newsletters" from lot of companies.

for antispam I also can recommend dspam, but it requires that every
user would learn system which mail is spam and which not.
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gordan at bobich

Dec 30, 2010, 12:22 PM

Post #14 of 19 (680 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

On 12/30/2010 05:54 PM, Tomas Kuliavas wrote:

>>>>> Can I collect opinions here about favorite/least favorite spam
>>>>> filtering packages, for use in a dbmail environment?
>>>>>
>>>>> What have you had luck with? What works best? What's your opinion?
>>>>> Which should a happy dbmail (postfix) user, now getting too much
>>>>> spam, use for filtration?
>>>>>
>>>>> TIA, Lou Picciano
>>>>>
>>>>> I'm using sqlgrey (postgrey implementation with database (mysql)) and
>>>>> spamassassin. So far so good. sqlgrey is the best tool (to my
>>>>> knowledge)
>>>>> for front-line protection against spam before spamassassin takes over
>>>>> the job. I'm welcome for other suggestions.
>>>> So, you don't mind not receiving mail from multi-homed hosts (*cough*
>>>> gmail *cough*)? Greylistting's very concept is broken by design.
>>>
>>> So using myriad of outgoing email servers is not something unusual.
>>
>> You are missing the point. Consider this scenario. A server has multiple
>> NICs on different networks, all routing to the internet. The default
>> route gets rotated around (when it expires, after a few minutes) in
>> order to load balance. This sort of a setup is fairly common on big
>> installations (helps with resiliency, too).
>>
>> So, such a server gets a message in it's outbound spool. It tries to
>> deliver it to you via one of it's several routes/NICs. You see the
>> connection, greylist it and temporarily reject. Server goes away for a
>> bit. By the time it retries, the route has expired, and you get an
>> incoming connection from the same server but from a different source IP.
>> Your greylist hasn't seen that IP, so you temporarily reject again. This
>> can go on forever. Some of your mail might get lucky and get through.
>> Most will probably get massively delayed, and some will likely keep
>> bouncing in the outgoing spool until it expires and bounces back,
>> several days later.
>
> So network design with routes that last less than couple of hours is
> perfectly ok? Trying to feed same email from different locations is
> exactly what spammer would do.

Equal cost routes rotate all the time, frequently on a per-TCP-session
basis. It's a perfectly legitimate, RFC compliant thing to do.

If spammers start to have heavily multi-homed zombies on a large scale,
that would arguably be pretty concerning.

>>> Anyone who does not like some tool can call it broken by design.
>>
>> You are mixing up cause and effect. I dislike tools if they are broken.
>> I don't call them broken because I dislike them.
>
> If you have information that tool has problems with some types of
> networking setups, you should say that it has problems with such setups.

Sure, and if you are happy to have unreliable service between your
servers and MSPs with multi-homed hosts, then you are welcome to break
your mail servers as much as you like. I don't really care.

> Tool works fine with other servers. Design is not broken. Calling
> something broken by design does not show what is broken in design. It only
> shows that you dislike the tool.

It's broken because it demonstrably fails, by it's very design, to work
reliably in a very real and valid scenario.

Gordan
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andrea at brancatelli

Dec 30, 2010, 12:47 PM

Post #15 of 19 (685 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

Propor calm down.

I'm using greylisting since ages and have no problem with gmail and such. Google uses mailnly 2, maybe 3 IPs. Mails may sometime arrive a bit later, it's true but it's not a serious issue...

Andrea Brancatelli
Inviato da iPad

Il giorno 30/dic/2010, alle ore 18:54, "Tomas Kuliavas" <tokul [at] users> ha scritto:

> 2010.12.30 19:29 Gordan Bobic rašė:
>> Tomas Kuliavas wrote:
>>
>>>>> Can I collect opinions here about favorite/least favorite spam
>>>>> filtering packages, for use in a dbmail environment?
>>>>>
>>>>> What have you had luck with? What works best? What's your opinion?
>>>>> Which should a happy dbmail (postfix) user, now getting too much
>>>>> spam, use for filtration?
>>>>>
>>>>> TIA, Lou Picciano
>>>>>
>>>>> I'm using sqlgrey (postgrey implementation with database (mysql)) and
>>>>> spamassassin. So far so good. sqlgrey is the best tool (to my
>>>>> knowledge)
>>>>> for front-line protection against spam before spamassassin takes over
>>>>> the job. I'm welcome for other suggestions.
>>>> So, you don't mind not receiving mail from multi-homed hosts (*cough*
>>>> gmail *cough*)? Greylistting's very concept is broken by design.
>>>
>>> So using myriad of outgoing email servers is not something unusual.
>>
>> You are missing the point. Consider this scenario. A server has multiple
>> NICs on different networks, all routing to the internet. The default
>> route gets rotated around (when it expires, after a few minutes) in
>> order to load balance. This sort of a setup is fairly common on big
>> installations (helps with resiliency, too).
>>
>> So, such a server gets a message in it's outbound spool. It tries to
>> deliver it to you via one of it's several routes/NICs. You see the
>> connection, greylist it and temporarily reject. Server goes away for a
>> bit. By the time it retries, the route has expired, and you get an
>> incoming connection from the same server but from a different source IP.
>> Your greylist hasn't seen that IP, so you temporarily reject again. This
>> can go on forever. Some of your mail might get lucky and get through.
>> Most will probably get massively delayed, and some will likely keep
>> bouncing in the outgoing spool until it expires and bounces back,
>> several days later.
>
> So network design with routes that last less than couple of hours is
> perfectly ok? Trying to feed same email from different locations is
> exactly what spammer would do.
>
>>> Anyone who does not like some tool can call it broken by design.
>>
>> You are mixing up cause and effect. I dislike tools if they are broken.
>> I don't call them broken because I dislike them.
>
> If you have information that tool has problems with some types of
> networking setups, you should say that it has problems with such setups.
> Tool works fine with other servers. Design is not broken. Calling
> something broken by design does not show what is broken in design. It only
> shows that you dislike the tool.
>
> --
> Tomas
>
> _______________________________________________
> DBmail mailing list
> DBmail [at] dbmail
> http://mailman.fastxs.nl/cgi-bin/mailman/listinfo/dbmail
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edacval at gmail

Dec 30, 2010, 12:56 PM

Post #16 of 19 (684 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

Hi
> It's broken because it demonstrably fails, by it's very design, to work
> reliably in a very real and valid scenario.
"very real" - for spammers and misconfigured setups.

"valid scenario" - really?

quote from http://tools.ietf.org/html/rfc5321#section-4.5.4.1 :
"
A client SHOULD keep a list of hosts it cannot reach and
corresponding connection timeouts, rather than just retrying queued
mail items.
"
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gordan at bobich

Dec 30, 2010, 2:39 PM

Post #17 of 19 (682 views)
Permalink

Re: Which spam filtering package do you think is best? [In reply to]

On 12/30/2010 08:56 PM, edacval [at] gmail wrote:
> Hi
>> It's broken because it demonstrably fails, by it's very design, to work
>> reliably in a very real and valid scenario.
> "very real" - for spammers and misconfigured setups.

gmail is a misconfigured setup and/or a major spam source? News to me.

> "valid scenario" - really?

Very.

> quote from http://tools.ietf.org/html/rfc5321#section-4.5.4.1 :
> "
> A client SHOULD keep a list of hosts it cannot reach and
> corresponding connection timeouts, rather than just retrying queued
> mail items.
> "

Sure. And when it eventually retries the IP it does so from may not be
the same one it tried from previously. Nowhere in the RFC does it say
that the sender must re-try from the same IP. If the IP is different,
this will fall foul of greylisting. The quote you pasted is in no way
relevant, it doesn't talk about the same case I was talking about.

It seems to me that you are erroneously (solipsistically?) concluding
that a problem doesn't exist just because you haven't noticed it. I can
only conclude that the reason for your not having noticed is either lack
of vigilance or the system you are dealing with is sufficiently small
that you were statistically lucky and haven't seen it yet (or
disregarded it as a glitch). Try with a user-count in the
100,000-500,000 range and this sort of thing starts to come up all over
the place.

If you think I'm making this up, google "greylisting gmail" and you'll
see that a lot of mail admins have bumped into this problem with
greylisting.

Gordan
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daniel at gosi

Dec 30, 2010, 3:59 PM

Post #18 of 19 (686 views)
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Re: Which spam filtering package do you think is best? [In reply to]

I wanted to add one of the solutions that work very well for me: ASSP

http://assp.sourceforge.net/

A open source anti spam tool written in perl, that includes a lot of ways to fight spam.
You may choose yourself which ones you would like to use or not. It works as a proxy in front of your MTA,
you bind your MTA to localhost or use a dedicated machine and let ASSP do the "outside" talking.
Many of the modules have test modes, so you can play around prior to activating them and well,
it really helped me a lot on the past 3 years. It of course had it bugs, just like dbmail had,
but the tool itself is well maintained. So if you find and error and report it, it will get fixed soonish.

One sad thing is that there website isn�t updated frequently.

It comes in two basic flavors:
ASSP v1.x
ASSP v.2.x

Version 2 has more features, is multithreaded but also consumes more resources.
Version 1 lacks some of the functionality, but works very nice as well ...

Give it a try ...

Cheers and a happy new year,
Daniel
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tokul at users

Dec 30, 2010, 8:16 PM

Post #19 of 19 (681 views)
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Re: Which spam filtering package do you think is best? [In reply to]

2010.12.31 00:39 Gordan Bobic rašė:
> On 12/30/2010 08:56 PM, edacval [at] gmail wrote:
>> Hi
>>> It's broken because it demonstrably fails, by it's very design, to work
>>> reliably in a very real and valid scenario.
>> "very real" - for spammers and misconfigured setups.
>
> gmail is a misconfigured setup and/or a major spam source? News to me.

They use other tools to fight spam and these tools are not without flaws
just like greylisting is.

They do break IMAP specification in their implementation of FETCH BODY
command or at least were breaking it several months ago. They do corrupt
some symbols in user input in their webmail or were doing it some time
ago. Not sure if they fixed it. Claiming that gmail is not misconfigured
is a very brave move.

--
Tomas

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