title: htmlentities returning empty string
body: <p>The following code outputs an empty string. The cause is the "ó" in $text, but why? What characters does utf-8 encode then?</p>
  
  <p>The problem is solved when using iso-8859-1, but I need to use utf-8, so what am I doing wrong?</p>
  
  <pre><code>&lt;!doctype html&gt;
  &lt;head&gt;
    &lt;meta charset="utf-8"&gt;
  &lt;/head&gt;
  
  &lt;body&gt;
  &lt;?
  $text = 'Hola ó Hola';
  $text = htmlentities($text,ENT_QUOTES,'utf-8');
  echo $text;
  ?&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>