Ah-ha, Success!

 

Yes, your code change worked, still not sure why my code didn't but it helped me zero in on another issue. In IE7 you don't seem to be able to directly write to the onclick event of an object instead you need something like this:

 

  <input id="clicker" type="button" value="Click Me" />

  <script language="javascript" type="text/javascript">
    document.getElementById('clicker').attachEvent('onclick', sayHello);
    function sayHello() {
      alert('hi');
    }

  </script>