How to get the number of weeks in a particular year? Also how to get the current year using zend?

1   <?php
2   // get number weeks of year for 2008
3   // result 52
4   ec开发者_如何转开发ho date("W", mktime(0,0,0,12,28,2008));
5   ?>

How can i get the above result , using zend functions .also how can i get hte current year using zend

<?php 
$date = new Zend_Date();
$date->setDay(31)->setMonth(12);
echo $date->toString("w");
?>