image1 = new Image();
image1.src = "images/button1_over.png";
image2 = new Image();
image2.src = "images/button2_over.png";
image3 = new Image();
image3.src = "images/button3_over.png";
image4 = new Image();
image4.src = "images/button4_over.png";
image5 = new Image();
image5.src = "images/button5_over.png";

function getYear() {
   tdate = new Date();
   return tdate.getFullYear();
}