--- modules/ecommerce/contrib/authorize_net/authorize_net.module	2007-02-20 18:34:05.000000000 +0530
+++ modules/ecommerce/contrib/authorize_net/authorize_net.module.new	2007-05-02 21:46:53.000000000 +0530
@@ -386,7 +386,7 @@ function authorize_net_form_submit($form
     }
   }
 
-  if ($t->shippable) {
+  if ($t->address['shipping']) {
     $d['x_ship_to_first_name'] = $t->address['shipping']->firstname;
     $d['x_ship_to_last_name'] = $t->address['shipping']->lastname;
     $d['x_ship_to_address'] = $t->address['shipping']->street1.' '.$t->address['shipping']->street2;