I also disagree with the assertion that clients on dsl/cable modems
should not be sending direct email. What they should not being doing
is sending direct email as bigisp.com (subject to the policy of the
ISP).
That depends both on the policy of the ISP and whether it's a static or
DHCP address. I don't think you'll find much support for direct sending
from DHCP addresses any more.
Regards,
John Levine, johnl(_at_)iecc(_dot_)com, Primary Perpetrator of "The Internet
for Dummies",
Information Superhighwayman wanna-be, http://iecc.com/johnl, Mayor
"I dropped the toothpaste", said Tom, crestfallenly.