Using account generator when importing project related invoices

We want to import project related invoices through the payables open Interface.

Since we also use the invoice workbench to manually create project related invoices, we want to use the same logic given by the account generating workflow (PAAPINVW) when importing invoices.

I can determine the project_id, task_id,expenditure_type,expenditure_item_date and expenditure_organization_id all right when populating the interface tables.

Yet, when simply leaving dist_code_concatenated and dist_code_combination_id blank, the import process generates a code combination from the default values defined in the accounting id flex field.

Is there any way to force invoice import to use the account generator workflow logic when creating the invoice (distributions)?