Use of DMAAI 4332 instead of 4340 at the voucher match of Outside Operation purchase order in foreig

At the voucher match of a purchase order in foreign amount related to the Outside Operation of a work order the system required the DMAAI 4332 instead of the 4340 so it is not possible to track in different accounts the variance due to the Exchange rate (DMAAI 4340) and the different PO price (DMAAI 4332).

Apparently the system uses the DMAAI 4332 for this purpose because in the item availability thre is zero quantity due to the off set of the OV with the OM in item ledger created at the receipt of the labor purchase order

We would like the system use the DMAAI 4340 in case of difference of Exchange rate if the foreign amount remains the same at the PO receipt and at the voucher match.