jQuery(document).ready(function($){

  $("#submenu li").hover(function () {
    if(this.className != "selected"){
      var file = $(this).find('img:first').attr("src");
      if(file){
        $src = file;
        $newsrc = getNewfile($src);
        $(this).find('img:first').attr("src",$newsrc);
    }
    $(this).find('ul:first').css({visibility: "visible",display: "none"}).slideDown("fast");
    }
  },function () {
    $(this).find('ul:first').css({visibility: "hidden"});
    $(this).find('img:first').attr("src",$src);
  });

})

function getNewfile(src){
  var ftype = src.substring(src.lastIndexOf('.'), src.length);
  var hsrc = src.replace(ftype, '_o'+ftype);
  return hsrc;
}