-<p>Move everything to using service strings rather that port
-numbers, so we can get rid of ENABLE_INET6 everywhere but in
-SockOpen (this will get rid of the kluge in rcfile_y.y).</p>
-
-<p>John Summerfield suggests that specifying a localname containing
-@ ought to be treated as an smtpname option, with the domain part
-removed for other purposes such as local-address matching.</p>
-
-<p>The <a
-href="http://bugs.debian.org/cgi-bin/pkgreport.cgi?pkg=fetchmail&archive=no">
-Debian bug-tracking page for fetchmail</a> lists other bug
-reports.</p>
+<p>Maybe refuse multidrop configuration unless "envelope" is _explicitly_
+configured (and tell the user he needs to configure the envelope
+option) and change the envelope default to nil. This would
+prevent a significant class of shoot-self-in-foot problems.</p>
+
+<p>Given the above change, perhaps treat a delivery as "temporarily
+failed" (leaving the message on the server, not putting it into
+.fetchids) when the header listed in the "envelope" option is not
+found. (This is so you don't lose mail if you configure the wrong
+envelope header.)</p>
+
+<p>Matthias Andree writes:</p>
+
+<blockquote>
+<p>NOTE that the current code need optimization, if I have
+unseen articles 3 and 47, fetchmail will happily request LIST for
+articles 3...47 rather than just 3 and 47. In cases where the message
+numbers are far apart, this involves considerable overhead - which
+could be alleviated by pipelining the list commands, which needs
+either asynchronous reading while sending the commands, or knowing the
+send buffer, to avoid deadlocks. Unfortunately, I don't have the time
+to delve deeper into the code and look around.</p>
+
+<p>Note that such a pipelining function would be of universal use, so it
+should not be in pop3.c or something. I'd think the best approach is to
+call a "sender" function with the command and a callback, and the sender
+will call the receiver when the send buffer is full and call the
+callback function for each reply received.</p>
+
+<p>See the ESMTP PIPELINING RFC for details on the deadlock avoidance
+requirements.</p>
+</blockquote>