title: PHP DateTime Update
body: <p>I'm using PHP > 5.3 and i have a question regarding DateTime:</p>
  
  <p>First i'm not able to use: </p>
  
  <pre><code>$date   = new DateTime('2012-06-08 00:00:00');
  $t = $date-&gt;createFromFormat('Y/m/d', '2012-06-11 23:59:59');
  </code></pre>
  
  <p>I get the following error message:</p>
  
  <blockquote>
    <p>Call to undefined method DateTime::createFromFormat()</p>
  </blockquote>
  
  <p>I can use other function in that class.</p>
  
  <p>The second thing i'm puzzled about how to update the object initial date, or do i have to create a new object?</p>