title: Not getting change events when radio buttons are clicked
body: <p>Mates,
  I'm tryin' to set backbone events when radio buttons are clicked.
  I have the following buttons:</p>
  
  <pre><code>&lt;p&gt;&lt;label for="pays"&gt;Pays now&lt;/label&gt;&lt;input id="pays" name="pays" type="radio" value="1" class="_100"/&gt;&lt;/p&gt;
  &lt;p&gt;&lt;label for="pays2"&gt;Pays later&lt;/label&gt;&lt;input id="pays2" name="pays" type="radio" value="2" class="_100"/&gt;
  </code></pre>
  
  <p>And I define the event like this:</p>
  
  <pre><code>'click input[name=pays]:not(:checked)': 'radioChecked'
  </code></pre>
  
  <p>So, as I understand it, it should fire when clicking an input named pays that's not checked.</p>
  
  <p>The thing is, that is not firing any event when I click on a radio button.</p>
  
  <p>If I try this...</p>
  
  <pre><code>'click input[name=pays]': radioClicked
  </code></pre>
  
  <p>I can fix this with some flags, but i'll have the event fired every time any radio is clicked.</p>
  
  <p>Any idea?
  Thanks!</p>