On 13/11/2008 13:09, "Franck Martin" <franck at avonsys.com> wrote: > I feel, there is a need to have a protocol working before advising it as a > best practice. AOL, Cloudmark, Hotmail, Yahoo!, and many others have had it working for years. It's often called a reputation system, and is regularly discussed at MAAWG and other fora.