That stops rather too many gateways. The problems you describe are due
specifically to mail<->news (ie. bidirectional) gateways. I'm using a
mail->news (unidirectional) gateway so my address won't match any
subscriber's address. I'm not causing your problems however (since the
software isn't there that could cause a mail loop) so why should I be
banned from the list? Besides, if you try and enforce a rule like the
one that you suggest, the chances are that start getting gateways that
rewrite From lines to be the subscriber's address. This is a recipe
for disaster.
> I know that some people are attached to reading through news, but
> surely it can't be that hard to get it via email?
It may be against a site's local policy to allow people to subscribe
to mailing lists. (I'm, thinking particularly of Universities that
don't want to donate the disk space for 1000 subscribers to high
volume lists.)
Peter