Magento Active states in TOP MENU

<?php 
 $_currentUrl = Mage::helper('core/url')->getCurrentUrl();
 $_homeUrl = Mage::helper('core/url')->getHomeUrl();
?>
 <div class="nav-container">
<ul id="nav">
<?php echo $_menu; ?>  
     <li class="level0 nav-1 level-top <?php if ($_currentUrl === $_homeUrl.'contact'):?> active<?php endif;?>"><a href="<?php echo $this->getUrl('contact')?>"><?php echo  $this->__('Contact Us') ?></a> </li>
</ul> </div>
 
 
 <?php endif ?>