title: Joomla 3.1 - JToolbarHelper: image of custom button not displayed/shown
body: <p>I am developing a component for <strong>Joomla 3.1</strong> and I am having some hard time in adding an image to the JToolbarHelper::custom() button....Based on this <a href="http://cjoomlatemplates.blogspot.com/2013/05/creating-toolbar-for-your-component.html" rel="nofollow">tutorial</a>, I am using the following code:</p>
  
  <pre><code>JToolBarHelper::custom( '', '../administrator/components/com_hmi/assets/css/icon-32-window.png', 
                      '../administrator/components/com_hmi/assets/css/icon-32-window.png', 'Window', true);
  </code></pre>
  
  <p>However the button and its text <strong>are displayed</strong> but not the button icon/image....Can someone help figure out whats wrong.  I have tried some other solution but got the same result :/</p>