--- a/dovecot-example.conf	Mon Jul 31 02:07:46 2006 +0300
+++ b/dovecot-example.conf	Mon Jul 31 02:12:51 2006 +0300
@@ -1001,4 +1001,13 @@
   # is a text file where each line is in format: <priority> <mailbox name>
   # Mails are first deleted in lowest -> highest priority number order
   #trash = /etc/dovecot-trash.conf
+
+  # Expire plugin. Mails are expunged from mailboxes after being there the
+  # configurable time. The first expiration date for each mailbox is stored in
+  # a dictionary so it can be quickly determined which mailboxes contain
+  # expired mails. The actual expunging is done in a nightly cronjob, which
+  # you must set up:
+  #   dovecot --exec-mail ext /usr/libexec/dovecot/expire-mails
+  #expire = Trash 7 Spam 30
+  #expire_dict = db:/var/lib/dovecot/expire.db
 }