diff --git a/addons/website_sale/models/sale_order.py b/addons/website_sale/models/sale_order.py
index ebc7bcab5b7608564dbd07211c8068c2223e03ff..8d2f51329e7e5d9533e3339ac12c755572891b60 100644
--- a/addons/website_sale/models/sale_order.py
+++ b/addons/website_sale/models/sale_order.py
@@ -193,7 +193,7 @@ class website(orm.Model):
                 values.update(sale_order.onchange_pricelist_id(pricelist_id, None)['value'])
                 sale_order.write(values)
                 for line in sale_order.order_line:
-                    sale_order._cart_update(product_id=line.product_id.id, add_qty=0)
+                    sale_order._cart_update(product_id=line.product_id.id, line_id=line.id, add_qty=0)
 
             # update browse record
             if (code and code != sale_order.pricelist_id.code) or sale_order.partner_id.id !=  partner.id: