public function amazonCall()
    {
        $sOperation = $this->_getOperationName();

        if ($sOperation !== false) {
            $oResult = $this->_getContainer()->getClient()->{$sOperation}(
                $this->_getOrder(),
                $this->_getParams()
            );

            $this->_addToMessages('<pre>'.print_r($oResult, true).'</pre>');
            return;
        }

        $this->setViewData(array(
            'sError' => 'Please specify operation you want to call (&operation=) '
                .'and use &oxid= parameter to specify order ID or use &aParams[\'key\']=value'
        ));
    }