Zend Feed with Custom namespace?

I am having a hard time creating a custom atom feed for my website using zend_feed class. Here is my FeedController class. Initially I tried to create a custom namespace in $feedArray but that doesn't seem to work. Later, I tried using registerNamespaces but the output is not as it is desired. Help me out!

public function indexAction(){    Zend_Feed::registerNamespace('mysite','http://dev.mysite.com');    $feedArray = array ('title' =>  'my siteFeed','link'  =>  'http://dev.mysite.com/feed','charset'   =>  'UTF-8','entries'   =>  array(),        );    $deals = new Application_Model_Deal();    $runningDeals = $deals->getRunning();    //print_r($runningDeals);    foreach ($runningDeals as $deal)    {        $feedArray['entries'][] = array ('title' => $deal['title'],              'link'  => 'dev.mysite.com/deals/'. $deal['slug'],'description' => $deal['description'],        );    }    $rssFeedFromArray = Zend_Feed::importArray($feedArray, 'atom');    $rssFeedFromArray->send();     $entry = new Zend_Feed_Entry_Atom();     $entry->title = 'my custom entry';     $entry->link = 'http://dev.mysite.com/feed';     $entry->charset    =   'UTF-8';     Zend_Feed::registerNamespace('mysite','http://dev.mysite.com');     $entry->{'mysite:title'} = 'Deal Title';             $entry->{'mysite:maxQuantity'} = $deal['max_purchase_individual'];             $entry->{'mysite:currentQuantity'} = 'qty';     echo $entry->saveXML();