I don't think it;s a duplicate of...because it doesn't have anything to do with audit ...i unninstall the audittrail module and it didn't changed anything...a put audit rules for purchase order, purchase order line and the same result. The only thing that work is to modify the function from purchase_order_line class def onchange_product_uom(self, cr, uid, ids, pricelist_id, product_id, qty, uom_id, partner_id, date_order=False, fiscal_position_id=False, date_planned=False, name=False, price_unit=False, notes=False, context=None): """ onchange handler of product_uom. """ if not uom_id: return {'value': {'price_unit': price_unit or 0.0, 'name': name or '', 'notes': notes or'', 'product_uom' : uom_id or False}} return self.onchange_product_id(cr, uid, ids, pricelist_id, product_id, qty, uom_id, - partner_id, date_order=date_order, fiscal_position_id=fiscal_position_id, date_planned=date_planned, + partner_id, date_order=date_order, date_planned=date_planned, name=name, price_unit=price_unit, notes=notes, context=context) Hope to improve in the addons. On Thu, Oct 4, 2012 at 1:42 PM, Amit Bhavsar (Open ERP) <