title: DateTime/DateInterval adding 25 hours each refresh gives a completely different result
body: <p>Here is my code:</p>
  
  <pre><code>$timezone = new \DateTimeZone('America/New_York');
      $date1 = new \DateTime (date("Y:m:d H:i:s", time()), $timezone);
      $date1-&gt;add(new \DateInterval ("PT24H"));
      echo $date1-&gt;format('Y-m-d h:s:m');
  </code></pre>
  
  <p>This should add 24 hours to the current time. Problem is, each time I refresh the page, I get a different result. And I don't mean by just a couple seconds like one would expect, I mean lots of minutes. Some above the actual time some below it.</p>
  
  <p>Three refreshes right now at 9:51pm give the following results: 2013-03-26 09:09:03, 2013-03-26 09:17:03, 2013-03-26 09:30:03</p>
  
  <p>Why can't I get the real time? What is going on?</p>
  
  <p>Thanks for the help!</p>