Someone using Thunderbird forwards e-mail messages to a local newsgroup.
Recently, these started appearing as .eml attachments with a MIME type
of application/x-mimearchive, which gnus doesn't know how to handle.
But if I use gnus-mime-view-part-as-type to view the attachment as
message/rfc822, it looks good.

1) Could Gnus be taught to treat these like message/rfc822, or something
like that?

2) If not, is there a way I can tell gnus to run
gnus-mime-view-part-as-type on every application/x-mimearchive part?

I have included such a posting as an attachment below.  It's the
part *within* the attachment below that I want to be able to view
without hitting any keys.

Thanks,

Dan