MIMEDefang is a flexible MIME email scanner designed to do all kinds of email processing, including anti-virus scanning, anti-spam scanning, replacing parts of messages with URLs, adding boilerplate disclaimers, and so on. It can alter or delete various parts of a MIME message according to a Perl-based policy filter. It can also bounce messages with unacceptable attachments and modify SMTP response codes on the fly. It works with the Sendmail 8.11 and newer "Milter" API, which makes it more flexible and efficient than procmail-based approaches.
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