title: PHP date returning wrong time
body: <p>The following script is returning the wrong time after I call <code>date_default_timezone_set("UTC")</code></p>
  
  <pre><code>&lt;?PHP   
      $timestamp = time();
      echo "&lt;p&gt;Timestamp: $timestamp&lt;/p&gt;";
  
      // This returns the correct time
      echo "&lt;p&gt;". date("Y-m-d H:i:s", $timestamp) ."&lt;/p&gt;";
  
  
      echo "&lt;p&gt;Now I call 'date_default_timezone_set(\"UTC\")' and echo out the same timestamp.&lt;/p&gt;";
      echo "Set timezone = " . date_default_timezone_set("UTC");
  
      // This returns a time 5 hours in the past
      echo "&lt;p&gt;". date("Y-m-d H:i:s", $timestamp) ."&lt;/p&gt;";
  
  ?&gt;
  </code></pre>
  
  <p>The timezone on the server is <strong>BST</strong>. So what should happen is that the second call to 'date' should return a time 1 hour behind the first call. It's actually returning a time 5 hours behind the first one. </p>
  
  <p>I should note that the server was originally set up with the EDT timezone (UTC -4). That was changed to BST (UTC +1) and the server was restarted. </p>
  
  <p>I can't figure out if this is a PHP problem or a problem with the server. </p>