Zipped multipart message over AS2

Hello all Webmethods experts

I would like to ask you for help with my problem with receiving messages over AS2.

Scenario: Our partner wants to send us encrypted and signed messages which will contain TEAPPS document and PDF document in one zip file over AS2. I have successfully established connection and I’m able to receive EDIINT and send MDN (also certificates for encryption are ok).
In webmethods portal-> transactions I’m able to see 3 rows per one message. 1st is info about EDIINT message which contains header with AS2 setup, 2nd is MDN which is ok and is sent back to partner nad third is PAYLOAD which is problematic, because it looks that EDDINT.receive service extracted it but paylod is not recognized and put to TN. Document type sender and receiver are unknown and also content is not readable.

EDDINT data have content type application/pkcs7-mime
in EDIINT message header is
content-disposition: attachment; filename=“smime.p7m”
Accept-Encoding: gzip,deflate

Payload contenttype text/plain; name=0000232058964
Payload mime headers Text/xml

in payload mime header is text/plain; name=0000232058964

I think that problem is in Payload content type which should be application/xml (because of TEAPPS which could be than recognized)
and content type is probably taken from payload mime header text/plain; name=0000232058964.
I was investigating from where webmethods are taking payload a nd it looks that these paramaters are taken from HTTP call

My questions are:
Is it even possible to have payload as .zip file and if yes can it contain documents together?
My assumption is that when content type will be set to XML document type should be recognized as TEAPPS document according to root tag and put to TN together with PDF part. When it will be in TN I can use my custom service to cut off PDF and save it separately with TEAPPS as a file to disk. Is my asumption wrong?
Why is payload not recognized? Is something wrong with contenttypes? Should it be changed in HTTP call?

Thank you in advance for your advices and explanations.
BR Jan Meliska

You can not send payload as .zip file. zip or pdf can only be sent as attachments.
As per your scenario, you can send TEAPPS document as payload with application/xml content type and the other pdf as attachment with application/pdf content type.