radio menu

radio menu

Hi, I'm using jQuery UI button(radio the 2nd option in examples) which work in Chrome and FF but not in IE.

here is mij code:
  1. $("input:radio").click(function(){      
  2.         var navval = $(this).attr('name');
  3.         alert( navval );
  4.         $.post("lib/PHP/sessionhandler.php", { menuselector: navval }, function(){
  5.             $("#menuDiv").load("lib/PHP/menu.php");
  6.         } );                
  7.     });


in IE the #menuDiv doesnt get refreshed. 
what am i doing wrong??

Thanks in advance Frank