Posted by Andy Hassall on 12/17/06 17:49

On Sun, 17 Dec 2006 09:10:30 -0800, "Vic Spainhower" <vic@showsec.com> wrote:

>I added additional content to the password request message which fixed the
>problem. The trim would not work.

Well, you must be adding those blank lines somewhere. They look weird as well
as the unintended side effect of setting off that particular SpamAssassin rule.

>Again, this is crazy that unless the
>message has some minimum number of characters it triggers it as SPAM.

It's the other way around, really. Weird formatting like lots of blank lines
is often indicative of it being generated by a computer program (after all, in
this case it's right, it was!), and that's more likely to be spam than not.
Generally the rules are developed by the spam filter developers by finding
common traits in spam email _and_ tuning them against a large volume of
recently collected spam; they're not just arbitrary rules.

Note that the blank lines rule only counted as a score of 1.5 or so, yet it
needed 5.0 to be classed as a spam. So it's just one of many factors that it's
taking into account. The Postini filter that you're trying to get it through
looks like it's set to be much too sensitive. None of the emails you sent to me
were flagged as spam on my system, they had low scores from just a couple of
rules.

>Is this why I often see a bunch of gibberish at the bottom of some spam emails?

Yes, the gibberish added at the end of spam emails is often to try and throw
off spam filters - usually it's to mess up Bayesian filters that learn words
and phrases that often appear in your email and use that as a factor to work
out if it's more or less likely to be spam. The spammers and the filters are in
a constant war against each other, and when people have spam filters set to be
be overly sensitive, then legitimate emails like yours can get caught in the
crossfire. It's a shame that the idiot spammers are destroying email like this,
but that's human nature for you.

--
Andy Hassall :: andy@andyh.co.uk :: http://www.andyh.co.uk
http://www.andyhsoftware.co.uk/space :: disk and FTP usage analysis tool

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