jQuery Dropdown Menu Issues. Please Help

jQuery Dropdown Menu Issues. Please Help

Hi. I've been struggling with a simple dropdown menu script. for some reason when i hover over the menu it expands fine but the minute i pass over a hyperlink that's behind the menu it registers the hover out function.

My jquery code is:
$(function() {
    //nav control
    $('.mainNav > li[class*=Nav]').hover(
      function() {
          $(this).find('a:first').addClass('hovering');
          $(this).find('ul').show();
      },
      function() {
          $(this).find('> ul').hide();
          $(this).find('a:first').removeClass('hovering');
      }
   );
});


My issue is strictly in IE7. works fine in IE8 and Firefox.

Thanks in advance!