Hello Sam,

>A number of our clients are also customers of webshoppe. Katrina, from 
>webshoppe, described you to me as their "email administrator".

Well, I help Webshoppe with their anti-mail abuse MX gateway I set up for 
them.  I find it useful to help them out because their abuse level was 
originally so bad, it was a huge challenge to set up the defenses.

Using the defensive techniques you are, amazingly, having trouble with, 
I've been able to defend Webshoppe's mail system from horrendous abuse 
traffic and re-establish a levels of increased reliability and reduced spam 
that are welcome to webshoppe and their users.

>When our product is sent to our clients daily, it is rejected by your 
>server at SMTP time with the message, "Message content rejected". Katrina 
>informed me that the message content is being rejected because of trailing 
>spaces at the end of the subject line.

yes, that's a very good filter for spammers who hang tracking ID's at the 
very end of Subject line:

Subject:  save $$$ on laserjet toner                      ERFJWEGWDD

and they also do this:

Subject:  save $$$ on laserjet toner......................ERFJWEGWDD

Subject:  save $$$ on laserjet toner----------------------ERFJWEGWDD

Subject:  save $$$ on laserjet toner. . . . . . . . . . . ERFJWEGWDD

>It would be an elaborate process to restructure our systems to strip off 
>the trailing spaces.

omygod, unbelievable, you can't do a "chomp" on an ascii string to clean 
off leading and trailing whitespace, without "restructuring your systems" 
?  Come on, Sam, you can't be serious.  I've been dealing with programmers 
for 30 years and every one would be embarrassed to make such a statement, 
if they had, in the first place, made the programming mistake of letting 
pointless whitespace leak into their printable output.

>Datafax has hundreds of clients who successfully recieve our report daily, 
>and who have done so for years. We are currently in the process of redoing 
>many of our systems, but at this time, our subject lines will keep their 
>trailing spaces.

Then, you are, simply and clearly, keeping a Subject: "signature" that is 
very common to spammers. Look like a spammmer, die like spammer.

Webshoppe's fixed string matching is dumbly simple and effective.  But 
every more sophisticated "heuristic" and "Bayesian" anti-spam weighting 
system includes signatures such as longs strings of repeating characters in 
the Sujbect:  line as weighing against this messages being legit.

>The specification for Internet Message Format as described in IETF 
>document RFC 2822 specifies parameters for the subject field in section 
>2.2.1. I will quote it below.
>
>"Unstructured Header Field Bodies: Some field bodies in this standard are 
>defined simply as "unstructured" (which is specified below as any US-ASCII 
>characters, except for CR and LF) with no further restrictions. These are 
>referred to as unstructured field bodies. Semantically, unstructured field 
>bodies are simply to be treated as a single line of characters with no 
>further processing (except for header "folding" and "unfolding" as 
>described in section 2.2.3)."
>I stress the part which says, "no further restrictions", which is 
>inclusive of the restriction against trailing spaces.

As a mail-based "e-company", you are very aware of the mail abusers who 
don't give flying F about RFC or IETF and friends.  As a result, ISP's like 
webshoppe suffer mightily.  Adminning a public email system isn't a chess 
game with tea and cakes, where we quote rule books at each other, call out 
"hear, hear, old chap, you mustn't do that.", and debate points of 
netiquette.  It's knife fight with NO RULES.

This stupid little "repeating character"  filter blocks dozens of crap 
messages every day, after all other filtering has failed. It's the last 
filter in the system.

>We would like to encourage you to bring your software into line with 
>existing and established Internet standards

Please direct such encouragement to spammers.  When they stop spamming us 
to death, then we can stop defending, and you can stop being 
(self-inflicted) collateral damage.

One unfortunate weakness in this particular "content scanning" filter is 
that we cannot whitelist messages, they all get scanned.  But, over the 
months, it has stopped 1000's of spam messages for Webshoppe.  You are the 
first and only legit emailer who refuses to quit looking like a spammer.

If Webshoppe tells me to take out this filter, I will.

I encourage you to find real programmers who can trim trailing whitespace 
from ASCII strings without having to restructure the entire system.

Len


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