Dovecot antispam plugin

This is a fork for dovecot 2.0.

The  dovecot  antispam plugin watches a defined spam folder (defaults to
"SPAM"). It works together with a spam system that classifies each message as
it is delivered. When the message is classified as spam, it shall be delivered
to the spam folder, otherwise via the regular filtering  file  the user  may
have (maildrop, sieve, ...). Now the user has everything classified as spam in
the special spam folder, everything else where it should be sorted to.


Authors:
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    Eugene Paskevich
    Johannes Berg
    Frank Cusack
    Benedikt Boehm
    Andreas Schneider