And there was much rejoicing..:
"The Apache Software Foundation is pleased to announce the release of SpamAssassin 3.0. SpamAssassin 3.0 contains a number of new technologies designed to protect against the changing techniques used by spammers. This is the first SpamAssassin release as an Apache Software Foundation project and under the Apache License. The release is available from the Apache SpamAssassin web site (http://spamassassin.apache.org/) via the Apache mirror network.
SpamAssassin 3.0 delivers many new features including support for sender authentication using the Sender Policy Framework (SPF), checking for web links of known spam advertisers, a modular plugin architecture, improved SQL database support for storing user data in server installations, and improved email classification.
SpamAssassin's practical multi-technique approach, modularity, and extensibility continue to give it an advantage over other anti-spam systems. Due to these advantages, SpamAssassin is widely used in all aspects of email management. You can readily find SpamAssassin in use in both email clients and servers, on many different operating systems, filtering incoming as well as outgoing email, and implementing a very broad range of policy actions. These installations include service providers, businesses, not-for-profit and educational organizations, and
end-user systems. SpamAssassin also forms the basis for numerous commercial anti-spam products available on the market today."
Go get it: SpamAssassin