Comment 13 for bug 265930

Originator: NO

Just did a bit of digging. It looks like section 5.2 of RFC 2045 suggests
that missing content-types should be treated as:

  Content-type: text/plain; charset=us-ascii

While i agree that it would be better for the sending MUA to include an
explicit content-type for each mime part (i'm about to file a bug against
the MUA), it seems problematic for pipermail to refuse to render such a
part at all.