Mailman and windows-1256 headers

[Guybrand]

Hello,

We have a very reproductible problem with mailman on
our Debian mail server. Whenever a user sends a message
to a list which encodes at least one header using
windows-1256 charset, the message gets shunt by
mailman. Here are a few examples:

# strings /usr/local/mailman/qfiles/shunt/* | grep windows
Accueil =?windows-1252?Q?Lyc=E9ens_mercredi_17_mars_14h3?=
Annonce =?windows-1252?Q?Conf=E9rence_E=2E_CADOT_-_6_M?=
(these are subjects)

ToUC=?windows-1252?Q?Facult=E9_de_chimie?=
<email address hidden>
(this is a destination)

Configuration is Mailman version: 2.1.4, Debian 3.0 and
Python 2.1.3.

Any fix or suggestion?
Regards,
gb

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