title: JQuery to disable checkbox if another is checked
body: <p>I have one checkbox that shows a div if the user checks it.  That div contains 2 other checkboxes.  If one of those two checkboxes are checked, I want to disable the first checkbox.  Some hmtl: </p>
  
  <pre><code>        &lt;p&gt;&lt;input id="noneAboveCheck" type="checkbox" /&gt;None of the above&lt;/p&gt;
          &lt;div id="noneAbove" class="hidden"&gt;
            &lt;p&gt;&lt;input id="incarcerated" type="checkbox" /&gt;&lt;/p&gt;
            &lt;p&gt;&lt;input id="support" type="checkbox" /&gt;Blah Blah&lt;/p&gt;
          &lt;/div&gt;
  </code></pre>
  
  <p>And here my jQuery, the toggle for the div works, but not the disabling.  The alert was there for testing and it doesnt show either, so I assume my first line is incorrect:</p>
  
  <pre><code>    $('#noneAboveCheck').change(function () {                
        $('#noneAbove').toggle(this.checked);
      }).change();
  
      if ($('#incarcerated, #support').attr("checked")) {
        alert("hello");
        $('#noneAboveCheck').attr('disabled', true);
      } else {
        $('#noneAboveCheck').attr('disabled', false);
      }
  </code></pre>
  
  <p>One last thing, I am (unfortunately) still using jQuery 1.4, so I dont think I can use .prop().
  Thanks for all the help.</p>