> Secondly, it seems that listserv will only check the From: field in the > SMTP envelope on any message for subscriber validation. This makes it > relatively easy to masquerade an address on any mailer program that will > allow you to manipulate the header, allowing actions to be taken on > someone else subscription regardless of whether the list is open or > closed. It is not secure enough. Put this in your header: Send= Private,Confirm This requires each poster to confirm (via the "OK" mechanism) that the posting actually came from them.