You can import transactions into QuickBooks that contain a currency that is different from your home currency using Zed Axis. You must have multi currency switched on in the company preferences and be using a version of QuickBooks that supports multi currency. Note that the multi currency feature in the US edition of QuickBooks is different to the multi currency feature in pre-2010 non US editions of QuickBooks (ie Canadian, UK, Australian, etc). Depending on the country version that you are using you need to keep in the mind the following to successfully import multi currency transactions:
New Mutlicurrency Module (US Editions of QuickBooks & QuickBook 2010 Canada & UK Editions)
When importing transactions that contain multiple currencies, QuickBooks will determine the currency to use based on the currency set on the Customer or Vendor record, it is not necessary to specify the currency however it is possible to specify an Exchange Rate that should be used for that particular transaction. The exchange rate is the market price for which this currency can be exchanged for the currency used by the QuickBooks company file as the "home" currency.
Old Multi-currency Module (applies to Canadian (pre 2010), UK (pre 2010) & Australian (all) Editions of QuickBooks).
When importing transaction data into non US editions of QuickBooks you cannot have a combination of currencies in the one import file you must only import transactions that are of the same currency. So that means all the Customers or Suppliers names must have the same currency on the QuickBooks record. Also it is not possible to map the Exchange Rate field and specify a different exchange rate to use other then what is set in the currency list in QuickBooks.
If you experience a problem please raise a support ticket.