function HoverImgOf(filename)
{
   var re = new RegExp("(.+)\\.(gif|png|jpg)", "g");
   return filename.replace(re, "$1_hover.$2");
}
function NormalImgOf(filename)
{
   var re = new RegExp("(.+)_hover\\.(gif|png|jpg)", "g");
   return filename.replace(re, "$1.$2");
}

$('#header').click(function() {
  window.location = $(this).attr("url");
    return false;
});