The solution is simple, proven, and works immediately (hours or days):
a significant group of managers (from firms on this list) agree and
announce that on a certain date and time, all mail will be bounced back
to IP addresses with a recent record of emitting spam, viruses, trojans etc.
(There are publicly available lists.)
This has been done in limited areas and it works immediately to force
the negligent providers to shut off all customers with dangerous boxes.
To repeat a previous post, those with a quiet moment you might wish to take
a look at
<http://www.camblab.com/nugget/spam_03.pdf>
and
<http://www.camblab.com/misc/univ_std.txt>
I'd welcome any comments.
Jeffrey Race