I am using the Google Checkout HTML api. I get the following error:
INPUT is:
title=Mr&firstname=Ian&lastname=Spence&email=ianspence%40gmail.com&facility=LSE&residence=Bankside&room=444&hireperiod=3&arrivaldate=10%2F04%2F2008&agreetc=on&item_name_1=Safe+Hire+at+LSE%2FBankside%2F444+for+Mr+Ian+Spence%2C+ianspence%40gmail.com+%2810%2F04%2F2008%29&item_description_1=LSE%2FBankside%2F444+%2810%2F04%2F2008%29&item_quantity_1=1&item_price_1=50.0&item_currency_1=GBP&checkout-flow-support.merchant-checkout-flow-support.shipping-methods.pickup-1.name=Safe+activated+on+arrival&checkout-flow-support.merchant-checkout-flow-support.shipping-methods.pickup-1.price=0.00&_charset_=ISO-8859-1&btnBuy.x=76&btnBuy.y=13
ERROR is:
_type=error&error-message=The+use+of+multiple+currencies+in+a+single+cart+is+unsupported+at+this+time.+You+supplied+a+cart+with+both+USD+and+GBP.&serial-number=24cccf19-5a48-44e4-b405-be7fa4e4fe6f
I am using the currency GBP for the item and the shipping.
It looks like a bug to me.