String editCartUrl = UtilProperties.getPropertyValue("googleCheckout.properties", "editCartUrl");
req.setContinueShoppingUrl(contShoppingUrl);
req.setEditCartUrl(editCartUrl);
// setup exempt tax support
TaxArea exemptArea = new TaxArea();
exemptArea.addWorldArea();
req.addAlternateTaxRule("tax_exempt", true, 0, exemptArea);
// setup default tax table
// TODO: implement this; for now use the tax table in Google Checkout Settings