Dave Thomas <Dave / PragmaticProgrammer.com> writes:

> Today, someone reported me for sending spam to the ruby-talk mailing
> list.

How about forwading only messages in the newsgroup that have some
certain custom headers?
For example:
X-Note-To-Gateway: This is not a spam. 

Then people in the newsgroup will be regularly informed (every 3
days?) to add this extra header or else their messages won't be
relayed to the ml.

YS.