Neill Newman neill@entora.co.uk writes:

I think that 4 is a little dificult, you can setup the mail server to use RBL/ORBS, but in my experience the spammers change addrees regularly an this becomes a little pointless

If the mail server uses RBL or ORBS and adds headers, we could hold any posts with the warning headers for approval.

Anyway, we're doing option 2 (restrict free posting to subscribed addresses), so make sure your subscription address (emailed to you last week) matches the address you use.