¿Cómo enviar un correo electrónico en magento escribiendo una acción en el controlador de índice?

mi controlador de índice;

public function postAction()
{           

    $post = $this->getRequest()->getPost();     
    if(!$post) exit;
    $translate = Mage::getSingleton('core/translate');
    $translate->setTranslateInline(false);
    try {
            $postObject = new Varien_Object();
            $postObject->setData($post);
            if (!Zend_Validate::is(trim($post['email']), 'EmailAddress')) {
                echo '<div class="error-msg">'.Mage::helper('contacts')->__('Please enter a valid email address. For example [email protected].').'</div>';
                exit; 
            }
            $storeId = Mage::app()->getStore()->getStoreId();
            $emailId = Mage::getStoreConfig(self::XML_PATH_SAMPLE_EMAIL_TEMPLATE);
            $mailTemplate = Mage::getModel('core/email_template');              
            $mailTemplate->setDesignConfig(array('area'=>'frontend', 'store'=>$storeId))
                ->setReplyTo($post['email'])
                ->sendTransactional($templateId, $sender, $email, $name, $vars=array(), $storeId=null)

            if (!$mailTemplate->getSentSuccess()) {                 
                echo '<div class="error-msg">'.Mage::helper('contacts')->__('Unable to submit your request. Please, try again later.').'</div>';
                exit;
            }               
            $translate->setTranslateInline(true);
            echo '<div class="success-msg">'.Mage::helper('contacts')->__('Your inquiry was submitted and will be responded to as soon as possible. Thank you for contacting us.').'</div>';
            }   
            catch (Exception $e) {
            $translate->setTranslateInline(true);
            echo '<div class="error-msg">'.Mage::helper('contacts')->__('Unable to submit your request. Please, try again later.').$e.'</div>';
            exit;
        }       
}

hay algún error ... por favor, ayúdame a salir de esto ... Gracias de antemano ...