"Marc-Adrian Napoli" spake unto me and said:
>
> What i'm after is a solution that falls into place at the
> qmail-send/qmail-local stage that will quickly check the
> headers of the message to be delivered locally first for
> any particular strings. (Silly email addresses or anything
> with the word "buy now" or "sell now" etc)
I recommend that you be _VERY_ careful with this idea,
especially if you are an ISP. In particular, bouncing
emails may anger your customers, and destroying emails
can get your butt sued off.
Suppose one of your customers is sent an email from his stock
broker, saying "Sell Now!!!!" Your customer never gets the
email, and loses his shirt, because of your spam "protection".
You will deserve whatever happens to you.
Other than RBL-blocking, and making sure _your_ relay is closed,
I recommend that you only use filters which are _explicitly_
approved by _each_ affected customer. Deciding for your
_customer_ which emails look "bad" to _you_ is very foolish.
Check out <http://www.pobox.com> for a good example of spam
filtering which is _customer_ approved.
Len.