README.textile in xero_gateway-2.0.13 vs README.textile in xero_gateway-2.0.14

@@ -220,17 +220,20 @@
       :reference => "YOUR REFERENCE (NOT NECESSARILY UNIQUE!)",
       :line_amount_types => "Inclusive" # "Inclusive", "Exclusive" or "NoTax"
     })
     invoice.contact.name = "THE NAME OF THE CONTACT"
     invoice.contact.phone.number = "12345"
-    invoice.contact.address.line_1 = "LINE 1 OF THE ADDRESS"    
-    invoice.add_line_item({
+    invoice.contact.address.line_1 = "LINE 1 OF THE ADDRESS"
+    
+    line_item = XeroGateway::LineItem.new(
       :description => "THE DESCRIPTION OF THE LINE ITEM",
-      :unit_amount => 1000,
-      :tax_amount => 125,
-      :tracking_category => "THE TRACKING CATEGORY FOR THE LINE ITEM",
-      :tracking_option => "THE TRACKING OPTION FOR THE LINE ITEM"
-    })
+      :account_code => 200,
+      :unit_amount => 1000
+    )
+    
+    line_item.tracking << XeroGateway::TrackingCategory.new(:name => "tracking category", :options => "tracking option")
+
+    invoice.line_items << line_item
 	
 		invoice.create</code></pre>