[Mailman-Users] Mailman + Exim + strange headers

[Stephen J. Turnbull]

Sergio Durigan Junior writes:

 > As you can see, the first two "Received:" headers got messed up somehow,

I don't understand what you mean by "messed up".  They looked
perfectly readable and RFC-conforming to me.

 > and the lines are not being prefix by \t but by one single space
 > char.

This is the RFC 5322 recommendation for folding header fields (use a
space, not a tab).

 > use Exim without Mailman, so maybe it is Mailman or some weird scenario
 > of Mailman + Exim modifying the e-mails without permission.

Older versions of Mailman (I'm not sure how old) are known to
sometimes modify the headers by unfolding them and then refolding them
when reassembling the message.  This may still be true of the most
recent versions.  I believe this is considered a bug but hard to fix,
and probably not worth fixing for that reason.  Is this actually
causing problems, or is it just ugly?