Alternate tax rate/area and new added line on Voucher match screen

Hello,

if a supplier has an alternate tax rate/area defined in F40081, this code is properly used on the purchase order, but on the voucher match screen P4314 if a new line is added (option 4), the system uses tax rate/area from the supplier definition F0401 instead of from F40081. I would expect that the system will use the alternate tax rate/area in the same way as on standard voucher entry P0411. Is it a system bug or is the system designed in this way?

Thank you.

Martina