When working with a supplier with the cXML punchOut protocol handler for AX2012 you will need to consider the currencies that are being used and what the vendor will return.
If a currency code hasn’t been setup in AX then when the user returns he shopping basket data from the suppliers when site and they try to convert that to a requisition then they will get an error because the currency doesn’t exist in AX. We added a parameter to do a check for the currency and to default it to the currency setup on the ledger.
This may not be accurate so you need to consider how you implement this because the currency means something and changing it has a different business effect. So consider making sure you setup any currencies you agree to work with the suppliers in the currency table in AX.
For notes on downloading the cXML punchOut protocol for AX2012 see this post