Bill in foreign currency - GnuCash 2.3.14

[Markus Scheffler]

Hi all,
can please somebody from the dev team check whether the billing function is working properly with foreign currency involved. Perhaps I am doing something wrong. My situation is as follow:
A/P account in USD
Expense account in JPY
Vendor in USD
Somehow I am not able to get the correct JPY amount in the expense account. Pay invoice seems to work correctly.
Thanks for your time,
Markus