title: Cakephp comment form input keeps the same value after i press add
body: <p>I've created a blog site from "Beginning CakePHP from novice to professiona"-David Golding. I have the comment view listed below:</p>
  
  <pre><code>&lt;div class="comments form"&gt;
  &lt;?php echo $form-&gt;create('Comment');?&gt;
      &lt;fieldset&gt;
          &lt;legend&gt;&lt;?php __('Add Comment');?&gt;&lt;/legend&gt;
      &lt;?php
          echo $form-&gt;input('name');
          echo $form-&gt;input('content');
          echo $form-&gt;input('post_id');
      ?&gt;
      &lt;/fieldset&gt;
  &lt;?php echo $form-&gt;end('Submit');?&gt;
  &lt;/div&gt;
  &lt;div class="actions"&gt;
      &lt;ul&gt;
          &lt;li&gt;&lt;?php echo $html-&gt;link(__('List Comments', true), array('action' =&gt; 'index'));?&gt;&lt;/li&gt;
          &lt;li&gt;&lt;?php echo $html-&gt;link(__('List Posts', true), array('controller' =&gt; 'posts', 'action' =&gt; 'index')); ?&gt; &lt;/li&gt;
          &lt;li&gt;&lt;?php echo $html-&gt;link(__('New Post', true), array('controller' =&gt; 'posts', 'action' =&gt; 'add')); ?&gt; &lt;/li&gt;
      &lt;/ul&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>The problem is after i press Submit the values remains in name and content fields.
  Can anybody help me?</p>
  
  <p>Thanks,</p>