Index: /lib/wpsg_basket.class.php
===================================================================
--- /lib/wpsg_basket.class.php	(revision 5600)
+++ /lib/wpsg_basket.class.php	(revision 5601)
@@ -630,5 +630,5 @@
 				if (isset($this->arCheckout['custom']) && wpsg_isSizedArray($this->arCheckout)) $data['custom'] = $this->arCheckout['custom'];
 						
-				if ($k_id > 0)
+				if (wpsg_isSizedInt($k_id))
 				{