[Mailman-Users] Trying to understand charset encoding in mailman

Mark Sapiro mark at msapiro.net
Thu Apr 17 14:33:06 CEST 2014

On 04/17/2014 04:19 AM, Laura Creighton wrote:
> But unless I have overlooked something, there is no way to make a charset
> change on a per-list basis through the mailman administrative interface.
> Instead you have to edit mm_cfg.py 


> Even if I had root access on python.org, I wouldn't really want to inflict
> utf-8 on everybody else just because it makes things more convenient for
> the EuroPython mailing list.
> But needing to edit mm_cfg.py strikes me as a very odd design choice, odd
> enough that I figure either a) this isn't so and I have overlooked something,
> or b) it absolutely must be done this way for a reason I do not understand.

There are a couple of issues.

Mailman was designed a long time ago in a galaxy far, far away (SciFi
ObRef). There was no Unicode or MIME in common use and email was ASCII
text. Everything was English and us-ascii.

When Mailman was internationalized, other languages required different
character sets so a scheme was developed where each translation had it's
own character set, but that for English was retained as us-ascii.

We can't give a list owner the ability to change the character set for a
list independent of the list language, because the templates and message
catalog for that language are encoded with a particular encoding, and
changing the character set without recoding the message catalog and
templates in the new character set would break everything.

The one exception to this is English. Because utf-8 is a strict superset
of us-ascii, one can change the charset for English to utf-8 and things
will continue to work. We haven't done that for reasons of superstition,
and because we use the Python email library which base64 encodes utf-8
text in message bodies rendering it unreadable by someone with a

Thus, a site can change the encoding for English to utf-8 if it chooses,
but there is no mechanism to do this per-list.

Mark Sapiro <mark at msapiro.net>        The highway is for gamblers,
San Francisco Bay Area, California    better use your sense - B. Dylan

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