title: Subscription error "Response does not match challenge"
body: <p>I set up a php server on a web host using this script I found from a website</p>
  
  <pre><code>&lt;?php
  
  define('VERIFY_TOKEN', 'DEVICETOKEN');
  $method = $_SERVER['REQUEST_METHOD'];
  
  if ($method == 'GET' &amp;&amp; $_GET['hub_mode'] == 'subscribe' &amp;&amp; $_GET['hub_verify_token']   == VERIFY_TOKEN) {
  echo $_GET['hub_challenge'];
  
  
  } else if ($method == 'POST') {
  $updates = json_decode(file_get_contents("php://input"), true);
  
  file_put_contents('/filepath/updates.txt',$updates, FILE_APPEND);
  
  error_log('updates = ' . print_r($obj, true));
  }
  
  ?&gt;
  </code></pre>
  
  <p>I used the realtime update panel on facebook to subscribe to a simple user email request as a test, I get this error everytime. </p>
  
  <pre><code>Response does not match challenge, expected value = '1098150855',
  received='1098150855&lt;!-- www.s...'
  </code></pre>
  
  <p>How do I solve this problem?</p>