function do_hovers() {
      //This function takes care of preloading and setting mouse events
      if (document.getElementsByTagName) {
            var images = document.getElementsByTagName('img');
            var preload_images = Array();
            for (var i=0; i< images.length; i++) {
                  if (images[i].className == 'rollover') {
                        cur_src = images[i].src;
                        images[i].off_src = cur_src;
                        images[i].over_src = cur_src.replace(/_inactive/g, '_active');
                        //alert(images[i].over_src);
                        preload_images[i] = images[i].over_src;
                        images[i].onmouseover = function() { this.src = this.over_src; };
                        images[i].onmouseout = function() { this.src = this.off_src; };
                  }
            }
            //preload the images
            document.preloaded_images = Array();
            for (var i=0; i<preload_images.length; i++) {
                  document.preloaded_images[i] = new Image;
                  document.preloaded_images[i].src = preload_images[i];
            }
      }
}