On Wed, 29 Dec 2010 09:33:25 -0800 Marc Perkel <supp...@junkemailfilter.com> wrote:
> Yes - there's no point in doing DNS blacklist lookups on yahoo, > hotmail, and gmail as well as thousands of other mixed source > providers. I disagree. I have a strong feeling that some of those providers route less-trustworthy mail through certain IP addresses and more-trustworthy mail through others. For example, some of Yahoo's servers are listed in our "good" list while others are listed in our "bad" list. The difference in observed behaviour between the two sets of Yahoo servers is very dramatic. We don't outright block hosts in the bad list, but we do add points. Regards, David.
