In have a person who is sending me mail with a multipart/mixed mail with this header:

--===============1505479739== Content-Type: text/plain; charset=unknown-8bit Content-Disposition: inline Content-Transfer-Encoding: 8bit

The problem is that RC doesn't show the contents of this part. Yes I know, it has a badly set charset, which I have already claimed to him about this configuration problem in his email client, but I guess there has to be some kind of failure-comeback to at least see something.

I haven't checked the code, but it sure looks like an encoding problem.