title: Jquery find checked input element inside a container not working in ie9
body: <p>I have created a custom checkbox of sorts . 
  It basically is a set of 2 checkboxes.When the dom is ready both the checkboxes are checked . The user is allowed to uncheck only one. </p>
  
  <hr>
  
  <p>This is how i went about implementing it.</p>
  
  <p>I have a container like so </p>
  
  <pre><code>&lt;div class="container"&gt;
       &lt;input name="my_checkbox_1" type="checkbox" checked="checked"&gt;
       &lt;label for="my_checkbox_1" class="on"&gt;Hello&lt;/label&gt;
       &lt;input name="my_checkbox_2" type="checkbox" checked="checked"&gt;
       &lt;label for="my_checkbox_2" class="on"&gt;World&lt;/label&gt;
  &lt;/div&gt;
  </code></pre>
  
  <p>now when a user clicks on label , i find the closest container</p>
  
  <pre><code>parent = $(this).closest(".container");
  </code></pre>
  
  <p>once i have the parent i find the number of checkboxes which are checked like so </p>
  
  <pre><code>len = $(parent).find("input:checkbox:checked").length;
  </code></pre>
  
  <p>if the len is 0 i try to alert the user with an appropriate error . This works in every other browser works but ie  (Am i allowed to say no surprise there ? ). but what am i doing wrong here ? </p>
  
  <p>Please do keep in mind , i have a number of such containers with checkboxes having unique names.</p>
  
  <p>I have created a fiddle with the code at 
  <a href="http://jsfiddle.net/kiranruth/UeEyB/1/" rel="nofollow">http://jsfiddle.net/kiranruth/UeEyB/1/</a></p>