I'm brand new here, feel free to take what I say with a grain of salt, ignore me altogether, etc.
Being brand-new, I'm not sure how big a problem this type of spamming is for you guys, but, the way we avoid it on Oracle-L, is that new subscribers are immediately subscribed to the list and start receiving email, but, new subscribers posting privs are disabled. In order to gain posting permissions, you're required to send a polite email, requesting it, to the Oracle-L admins (which is myself and Steve Adams, currently). The admin has to login to the website and explicitly enable posting privileges. It's a bit of a hassle, but, our signal to noise ratio is extremely high, and spamming is nearly impossible. If someone is a troublemaker, you can temporarily, or permanently ban them, and new subscribers can't take the hit-and-run approach of subscribing an account, spamming, and then abandoning the account.
It's a bit more work for the admins, but, speaking as one of the Oracle-L admins, and Oracle-L is a pretty busy list, the workload of granting new subscribers posting privileges is pretty low. Steve is pretty inactive these days, and I handle pretty much all the day-to-day stuff, and I get, around 1-4 requests for posting privileges a day. As I'm pretty active, I usually handle them as they come in, but, one could also just check the email once a day, at a specific time, and run through everything there.
I'm not sure how big this list is, how frequently you get new subscribers, etc, nor do I have any idea how big the spam problem is here, but, I thought I'd mention an idea for an alternate approach.
As I said, I'm brand new here, feel free to ignore all of the above....
From: Neil Beddoe
Sent: Thursday, March 25, 2010 1:04 PM
Subject: RE: spammer on dbi-users
They'll only use another address if you do. There are a lot of these originating from Hotmail accounts at the moment.
Sent: 25 March 2010 16:57
Subject: spammer on dbi-users
Who's ever the dbi-users group monitor, please shut this annoying person
Kenneth Webber <firstname.lastname@example.org>
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