How to set up a quantity based tax for a foreign currency AR invoice when the tax rate is in the fun

Dear Colleagues,

How to set up a quantity based tax for a foreign currency AR invoice when the tax rate is in the functional currency in R12 E-Business Tax?

R12.2.6 E-Business Tax (EBTax)

We migrated from 11i to R12.2.6. We had a PL/SQL formula for a quantity based tax in 11i.

Actually, that is the tax formula in PL/SQL of this quantity based tax in 11i:

arp_tax.tax_info_rec.tax_amount:=

round(arp_tax.tax_info_rec.taxed_quantity *

      arp_tax.tax_info_rec.tax_rate/arp_tax.tax_info_rec.trx_exchange_rate,2

     );

Now we have to replace it by the functionality of