diff --git a/addons/sale/sale.py b/addons/sale/sale.py
index 5eec3bc8b40..71366c5a3ab 100644
--- a/addons/sale/sale.py
+++ b/addons/sale/sale.py
@@ -644,6 +644,7 @@ class sale_order(osv.osv):
                 if line[2].get('product_id'):
                     taxes_id = product_obj.browse(cr, uid, line[2]['product_id'], context=context).taxes_id
                 elif line[1]:
+                    # don't change taxes if they are no product defined
                     taxes_id = line_obj.browse(cr, uid, line[1], context=context).product_id.taxes_id
                 if taxes_id:
                     line[2]['tax_id'] = [[6, 0, fiscal_obj.map_tax(cr, uid, fpos, taxes_id)]]
diff --git a/addons/website_sale/models/sale_order.py b/addons/website_sale/models/sale_order.py
index 1102016bacd..cd334a2c451 100644
--- a/addons/website_sale/models/sale_order.py
+++ b/addons/website_sale/models/sale_order.py
@@ -177,6 +177,10 @@ class website(orm.Model):
                 fiscal_position = sale_order.fiscal_position and sale_order.fiscal_position.id or False
 
                 values = sale_order_obj.onchange_partner_id(cr, SUPERUSER_ID, [sale_order_id], partner.id, context=context)['value']
+                order_lines = map(int,sale_order.order_line)
+                values.update(sale_order_obj.onchange_fiscal_position(cr, SUPERUSER_ID, [],
+                    values['fiscal_position'], [[6, 0, order_lines]], context=context)['value'])
+
                 values['partner_id'] = partner.id
                 sale_order_obj.write(cr, SUPERUSER_ID, [sale_order_id], values, context=context)