According to multiple sources inside Microsoft, they plan to release
the Exchange 2003 IMF (Inteligent Messaging Filter) for free via a web
download very soon. Previously it was announced that this would only
be available to those Microsoft customers who were part of their Software
Assurance program. It's good to see Microsoft took feedback from their
customers and decided to provide this to everyone at no cost. I'll post
a link to the download when it's available.