PMilter is an attempt to reimplement Sendmail's milter (mail filter) protocol in pure Perl. There are many reasons for this, including independence from Sendmail's libmilter, as well as freedom from POSIX threads (helps stability for Perl filters), etc. . Most of PMilter's Sendmail::Milter interface is a clone of the frontend functions in PMilter::Server. However, this compatibility package also includes some methods specific to the Sendmail MTA, which are deliberately not included in PMilter::Server.
