[Mailman-Users] Mailman converts the body of messages into attachments

[Athos Rothen]

	Hello All,

	I am using Mailman 2.1.5 and have this list that converts
text/html parts to plain text (content filtering options enabled). It
works fine for most of users/messages. But when some users, those that
use webmailers (yahoo, hotmail, outlook web access), send messages to
the list, the body of their messages is converted to plain text and it's
being attached into their messages.

My Content Filtering options are:
filter_content: yes
filter_mime_types: <blank>
pass_mime_types: multipart/mixed \ multipart/alternative \ text/plain
convert_html_to_plaintext: yes
filter_action: Discard

I searched the web, faqs and mailing lists, but looks like this is not a
common problem (I found only few similar cases, but most of them related
to digest).

Does anyone have a clue of what could be the problem? Or where should I
start to look for a solution/workaround?

Additional information: I am from Brazil and the language of the
messages is Portuguese. Some of the attachments have these MIMEs:

Ex1:
--===============1472294390==
content-class: urn:content-classes:message
Content-Type: text/plain; charset="Windows-1252"
Content-Transfer-Encoding: 8bit

Ex2:
--===============1423875694==
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

I do not know if it helps in some way, but I though it could be
relevant.

Thanks for any help!

Best Regards,
Athos Rothen
athos at conectt.com.br