I'm thinking you could also just moderate the entire list for a few days
(with "Send= Editor,Hold,Confirm") and eventually he might get tired of
the fact that you won't approve his messages, no matter <where> they
come from...
The kicker is that with all of these freebie e-mail providers (HOTMAIL,
BIGFOOT, etc) he could jump to one of them from JUNO, making even freezing
all JUNO users out a waste of time. And don't think he isn't that smart :)
You could also set
* Default-Options= REVIEW
in the list header and then it doesn't matter if he unsubs and resubs from
another address. Legitimate subscribers could be set NOREVIEW later, after
a probation period.
Nathan