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MIMEDefang is an e-mail filtering tool that works with the Sendmail "Milter" library. MIMEDefang lets you express your filtering policies in Perl rather than C, making it quick and easy to filter or manipulate your mail.

MIMEDefang is mature software: The first version was released in 2000. It's also in use in thousands of installations.

MIMEDefang is under active development; it forms the basis of our CanIt commercial anti-spam product.

MIMEDefang is free software: It's released under the terms of the GNU General Public License. It runs under Linux, FreeBSD, Solaris and most other UNIX or UNIX-like systems.