[Mimedefang] Mailing lists, ham, and broken MUA's

Philip Prindeville philipp_subx at redfish-solutions.com
Tue May 4 00:37:12 EDT 2010

RFC-2822 requires that a message be encoded in the smallest possible 
representation, if I remember, but few MUA's actually do this.

But a lot of broken MUA's (especially Outlook) get this wrong.

For instance, if I were to mail to the mimedefang mailing list this 
message, as is, but encoded as "gb2312", then that would be broken.

The problem is this: the message will be intelligible to English 
language readers, but it will generate a lot of false positives for 
mailing list recipients who aren't expecting to get non-English messages 
(or English messages encoded in anything other than USASCII, ISO-8895-1, 
or UTF-8).

Would it make sense for people using mailman or listmaster, etc. to pass 
the message through mimedefang to transcode the message body?

If the message body is Content-Type: text/plain; charset=xxxx should it 
be squashed down in the case of mailing list traffic for English 
language mailing lists?

No, I'm not trying to impose Anglophone xenophobia... as I said, this 
would only affect messages already written entirely in 7-bit ascii (or 
worse case Latin1 or it's alternative encodings such as Windows-1252).

Make sense?

The entire Perl logic to handle this wouldn't be more than 10 lines I 

for instance:

use Encode::First qw(encode_first);

my $encodings = join('ascii', 'latin1', 'utf-8', $oldcharset);

my ($newcharset, $newlen) = encode_first($encodings, $string);

if ($newlen<= length($string)) {
     # use $newstr instead

What does everyone think about doing this in mailing list exploder 



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