Comment 13 for bug 265847

TK, I've looked at the patch, and I like parts of it but not
other parts. For me, get_content_charset() always digs out
the right character set without the need for that regexp.
If it doesn't for you, then that's a bug in the email
package, which we should report and fix.

I've attached my tentative patch which seems to fix the
clasohlson mbox when using Czech. I haven't yet tried
attachment_error.mbox, and I haven't fixed the private
archiver or the mimetypes lie, but will get to those next.