BAPI_SALESDOCU_CREATEWITHDIA with partners does not work fine

Hi all,

we are using the BAPI_SALESDOCU_CREATEWITHDIA FM sending some parameters like sales org, distr. channel, division and parners (sold-to-party and ship-to-party).

The problem is that, if the user creates a new document using "create with reference", some fields are not filled at header level of the new sales document. These fields are not filled if we send partners in table SALES_PARTNERS when calling the BAPI. If we do not send any partners these fields are filled correctly.

The fields are "assignment" (VBAK-ZUONR) and "reference no." (VBAK-XBLNR) in "Accounting" tab.

We tried "call transaction" statement but we can't find a way to send partner numbers using this method.

Any help would be really appreciated. Thanks in advance.