title: Override Topmenu.php in magento
body: <p>I'm trying to override the _getHtml function in Mage_Page_Block_Html_Topmenu magento class</p>
  
  <p>I've created a new module in app/cod/local/MyModulo/Opage</p>
  
  <p>My congig.xml is:</p>
  
  <pre><code>&lt;config&gt;
  &lt;modules&gt;
      &lt;MyModulo_Opage&gt;
          &lt;version&gt;1.0.0&lt;/version&gt;
      &lt;/MyModulo_Opage&gt;
  &lt;/modules&gt;
  &lt;global&gt;
  &lt;blocks&gt;
      &lt;page&gt;
          &lt;rewrite&gt;
              &lt;html_topmenu&gt;MyModulo_Opage_Block_Html_Topmenu&lt;/html_topmenu&gt;
          &lt;/rewrite&gt;
      &lt;/page&gt;
  &lt;/blocks&gt;
  &lt;/global&gt;
  </code></pre>
  
  <p></p>
  
  <p>My class is:</p>
  
  <p>
  
  <p>But when I test it, the category top menu doesn't appear. What I'm doing wrong?</p>