How do I parse multipart/digest mails?

I'm trying to parse an old mail that is multipart/digest. When using the example "ExaminEml" I correctly get

multipart/mixed text/plain text/plain multipart/digest message/rfc822 message/rfc822 and so on. text/plain

as result.

But how do I access the parts with multipart/digest and message/rfc822? Both GetPlainTextBody and GetHtmlBody only have the text/plain part. NumAttachedMessages is 0. I've uploaded the email to http://www.mothsoftware.com/downloads/digest.eml .

Xojo 2016r4.1, MacOS 10.11.6, latest Chilkat plugin.

Mit freundlichen Grüßen/Regards

Beatrix Willius

http://www.mothsoftware.com Mail Archiver X: The email archiving solution for professionals