Fill payload into SNDPRN

Hello,

I know, it is a old problem, but mayber I have something overseen.

Scenario: XML ->XI->Idoc Adapter to R/3

I want to fill the field SNDPRN of the control record with a value of the XML payload.

I can not work with header mapping or identifiers, as the messages come from the same sender party and service.

But I need different partner profiles in the R/3 system, and the partner name is in the payload of the message.

Does anybody know how this can work?

How can I prevent the IDOC adapter from overwriting the value I fill into SNDPRN in the mapping....

best regards

Werner