Adding new fields that are not available in the PO CXML XSD file to the OBN PO CXML output file

Summary:

We have added Mailing Address details in the Manage Locations FSM task that we want to add to the PO CXML file that is transmitted to the supplier via OBN.

Secondly, we have added DFF in Requisition header BUT we are not copying the Req DFFs to PO (due to Oracle limitation that disallows to merge multiple non-catalog PRs by buyer). However, We want to send this requisition DFF value in the PO CXML output to supplier.

We've exported the PO CXML transformation package and checked the XSD files. They do not have the above required fields. But, it is possible to add new fields to the XSD file?