i am using FlashMessenger helper to set messages, but i am unable to retrieve messages using getMessages() method. it returns null. here is my sample code:

```
<?php
class Admin_TestController extends Zend_Controller_Action
{
    protected $_flashMessenger = null;

    public function init()
    {
        $this->_flashMessenger = $this->_helper->getHelper('FlashMessenger');
        $this->initView();
    }

    public function myAction()
    {
        $this->_flashMessenger->addMessage('test message');

        $this->_helper->Redirector("mynextrequest");
    }

    public function mynextrequestAction()
    {
        zend_debug::dump($this->_flashMessenger->getMessages());
        $this->render();
    }
}

```