I think this bug was reported upstream, https://bugs.launchpad.net/mailman/+bug/1189558 <https://bugs.launchpad.net/mailman/+bug/1189558>. If that upstream bug is relevant to this bug report, then it was fixed in mailman 2.1.16, and this bug could probably be closed. I’ve tested the wheezy backport 2.1.18 packages, and they fixed this problem for me.

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Geoff Crompton, Senior ICT Infrastructure Administrator
T: +61 (0)3 9348 7138
Trinity College | University of Melbourne | Royal Parade, Parkville | Victoria 3052, Australia
www.trinity.unimelb.edu.au <http://www.trinity.unimelb.edu.au/>