title: jpgraph doesn't work
body: <p>I am developing a web application about statistics, so I am using the library <a href="http://jpgraph.net" rel="nofollow">jpgraph</a></p>
  
  <p>What is going wrong is that the graph does not appear. Displays only the browser's broken image icon.</p>
  
  <pre><code>$num  = 20;
  $num2 = 10;
  $data = array($num,$num2);
  
  $graph = new PieGraph(300,200);
  $graph-&gt;SetShadow();
  $graph-&gt;title-&gt;Set("Utilizadores Registados");
  
  $p1 = new PiePlot($data);
  $graph-&gt;Add($p1);
  $graph-&gt;Stroke();
  </code></pre>
  
  <p>I am sure that GD is enable.</p>
  
  <p>Thank you!</p>