This option controls what Mailman does to the
<tt>Reply-To:</tt> header in messages flowing through this
mailing list. When set to <em>Poster</em>, no <tt>Reply-To:</tt>
header is added by Mailman, although if one is present in the
original message, it is not stripped. Setting this value to
either <em>This list</em> or <em>Explicit address</em> causes
Mailman to insert a specific <tt>Reply-To:</tt> header in all
messages, overriding the header in the original message if
necessary (<em>Explicit address</em> inserts the value of <a
href="?VARHELP=general/reply_to_address">reply_to_address</a>).
<p>There are many reasons not to introduce or override the
<tt>Reply-To:</tt> header. One is that some posters depend on
their own <tt>Reply-To:</tt> settings to convey their valid
return address. Another is that modifying <tt>Reply-To:</tt>
makes it much more difficult to send private replies. See <a
href="http://www.unicom.com/pw/reply-to-harmful.html">`Reply-To'
Munging Considered Harmful</a> for a general discussion of this
issue. See <a
href="http://www.metasystema.net/essays/reply-to.mhtml">Reply-To
Munging Considered Useful</a> for a dissenting opinion.
<p>Some mailing lists have restricted posting privileges, with a
parallel list devoted to discussions. Examples are `patches' or
`checkin' lists, where software changes are posted by a revision
control system, but discussion about the changes occurs on a
developers mailing list. To support these types of mailing
lists, select <tt>Explicit address</tt> and set the
<tt>Reply-To:</tt> address below to point to the parallel
list.
