if (document.images)
{
  button1over = new Image;
  button1over.src = "images/btn_start_over.gif";
  button2over = new Image;
  button2over.src = "images/btn_search_over.gif";
  button3over = new Image;
  button3over.src = "images/btn_signup_over.gif";
  button4over = new Image;
  button4over.src = "images/btn_profile_over.gif";
  button5over = new Image;
  button5over.src = "images/btn_search_again_over.gif";
  button6over = new Image;
  button6over.src = "images/btn_apply_over.gif";
}