[Dovecot] multiple ports, different characteristics

[WJCarpenter]

The wiki <http://wiki.dovecot.org/Iptables> leads me to believe that
the only way to configure dovecot to listen for the same protocol on
multiple ports is via external redirection (iptables or similar).  Is
that so, or can dovecot be directly configured to listen on multiple
ports?

Here's a concrete example of what I'm trying to accomplish.  Our
environment uses plaintext authentication, and so we force our users
to use TLS for IMAP.  For some internal connections (specifically with
dovecot built-in proxying), we need non-TLS connections for IMAP.
It's completely OK here if we need to listen on different ports for
the two flavors of connections.

Can dovecot be configured to handle this and/or do we need to run
multiple instances of dovecot with different config files?

Thanks
-- 
bill-dovecot at carpenter.ORG (WJCarpenter)    PGP 0x91865119
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