href and onclick not playing nice in mobile safari

href and onclick not playing nice in mobile safari

a test as simple as the following is not behaving as expected (show the alert) on iPhone/iPad. 
Works on all other browsers and also the iPhone simulators.
  1. <a id="trigger_a" onclick="return false;" href="jsnotworking" >
  2. <h1>Click here</h1>
  3. </a>
  4. <script type="text/javascript">
  5.      $(document).ready(function(){
  6.                            $("a").click(function(event){
  7.                                    alert('now!');
  8.                                    });
  9.                        });
  10. </script>
Does Mobile Safari/iOS have a different event handling model? 
Any help is much appreciated.
Thanks