[Pkg-mailman-hackers] Bug#756323: mailman: why does mailman now include original From header in Reply-to?

[Joe Pfeiffer]

Package: mailman
Version: 1:2.1.18-1
Severity: normal

Somewhere between versions 1:2.1.15-1 and the current 1:2.1.18-1,
mailman added code to always include the original From header in
mailman's Reply-to header.  Before calling this a bug, I'm curious as
to why (if it's in the changelog, I missed it).

For a list I administer, this has the following consequence:
Member1 sends message to list
Mailman sends message to all members, with reply-to set to original
sender and list
Member2 replies to message.  Sending message to original Member1
explicitly and to list.
If Member1 has set DontReceiveDuplicates, then Member1 receives copy
of message sent directly, but not copy sent through mailman.  This
copy doesn't have Reply-To set to the list.
Member1 replies to Member2's message, sending to Member2 but not list.

The code is in Mailman/Handlers/CookHeaders.py, lines 172-174.
        # We also need to put the old From: in Reply-To: in all cases.          
        if o_from:
            add(o_from)

-- System Information:
Debian Release: jessie/sid
  APT prefers testing
  APT policy: (700, 'testing'), (650, 'stable'), (600, 'unstable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.14-1-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages mailman depends on:
ii  apache2                2.4.9-2
ii  apache2-bin [httpd]    2.4.9-2
ii  cron                   3.0pl1-124.1
ii  debconf [debconf-2.0]  1.5.53
ii  libc6                  2.19-7
ii  logrotate              3.8.7-1
ii  lsb-base               4.1+Debian13
ii  python-dnspython       1.11.1-1
pn  python:any             <none>
ii  ucf                    3.0030

Versions of packages mailman recommends:
ii  exim4-daemon-light [mail-transport-agent]  4.82.1-1+b1

Versions of packages mailman suggests:
ii  listadmin     2.40-4
ii  lynx          2.8.9dev1-2
pn  spamassassin  <none>

-- Configuration Files:
/etc/mailman/apache.conf [Errno 2] No such file or directory: u'/etc/mailman/apache.conf'

-- debconf-show failed