public function insertEmailListRecipient($recipient, $uri = null)
    {
        if ($uri === null) {
            require_once 'Zend/Gdata/App/InvalidArgumentException.php';
            throw new Zend_Gdata_App_InvalidArgumentException(
                    'URI must not be null');
        } elseif ($uri instanceof Zend_Gdata_Gapps_EmailListEntry) {
            $uri = $uri->getLink('edit')->href;
        }
        $newEntry = $this->insertEntry($recipient, $uri, 'Zend_Gdata_Gapps_EmailListRecipientEntry');
        return $newEntry;
    }