title: CakePHP Cache::clear does not work
body: <p>I have a Cache Configuration in my bootstrap.php file as</p>
  
  <pre><code>Cache::config('long', array(
          'engine'     =&gt; 'File',
          'duration'   =&gt; '+1 week',
          'probability'=&gt; 100,
          'mask'       =&gt; 0666,
          'path'       =&gt; CACHE . 'long' . DS,
      ));
  </code></pre>
  
  <p>and i am trying to clear cache when a setting is edited. Below is my admin_edit function</p>
  
  <pre><code>public function admin_edit($id = null) {
          if (!$this-&gt;Setting-&gt;exists($id)) {
              throw new NotFoundException(__('Invalid setting'));
          }
          if ($this-&gt;request-&gt;is('post') || $this-&gt;request-&gt;is('put')) {
              if ($this-&gt;Setting-&gt;save($this-&gt;request-&gt;data)) {
                  $this-&gt;Session-&gt;setFlash(__('The setting has been saved'));
                  $this-&gt;redirect(array('action'=&gt; 'index'));
                  Cache::clear(false,'long');
                  Cache::gc();
              }else {
                  $this-&gt;Session-&gt;setFlash(__('The setting could not be saved. Please, try again.'));
              }
          }else {
              $options = array('conditions' =&gt; array('Setting.' . $this-&gt;Setting-&gt;primaryKey=&gt; $id));
              $this-&gt;request-&gt;data = $this-&gt;Setting-&gt;find('first', $options);
          }
      }
  </code></pre>
  
  <p>However, <code>Cache::clear(false,'long')</code> does not work and it does not clear the Cache. Not sure what is going wrong. Stuck for a few days now!</p>