Accounting date on AP Invoice lines

Hi

Is there any way to make the Accounting Date in the Match zone of the AP workbench default to the GL date on the PO Shipment?

Client has PO shipment GL date Jan-12, Received Nov-11, invoice received and entered and header GL date Nov-11, but wants the invoice distributions to have GL date Jan-12 the same as the PO.

POs are Expense, not Inventory.

AP and PO periods are open for Jan-12, GL is future entry.

AP, PO and GL are open for Nov-11.

Thanks

Ian