Am not aware of any standard way to do this using a single currency code.
One way to do this may be to create different currency codes for use in A/P
and A/R.
If your base currency is AUD for example, and you want to trade in NZD with
suppliers and customers then you could use=20
a curency code of NZS (for example) for Suppliers and NZC for customers.
You could then set differing exchange rates for these currency codes and set
the currency codes in the Supplier Master (NZS) and Customer Master (NZC).
May need to consider effects on Purchase Orders and Invoices, but if using a
forms package to re-format documents going to outside parties, then a rule
could be set within the forms software.
Regards,
Adrian Skuodas