var preLoadImg = new Object();

function initRollOvers(){
	$("img.rollover").each(function(){
		var imgSrc = this.src;
		var sep = imgSrc.lastIndexOf('.');
		var onSrc = imgSrc.substr(0, sep) + '_o' + imgSrc.substr(sep, 4);
		preLoadImg[imgSrc] = new Image();
		preLoadImg[imgSrc].src = onSrc;
			$(this).hover(
				function() { this.src = onSrc; },
				function() { this.src = imgSrc; }
			);
		});
	}
$(function(){
	initRollOvers();
});

var preLoadImg = new Object();
 function smartRollover() {  
     if(document.getElementsByTagName) {  
          var images = document.getElementsByTagName("img");  
          for(var i=0; i < images.length; i++) {  
              if(images[i].getAttribute("src").match("_off."))  
              {  
                  images[i].onmouseover = function() {  
                      this.setAttribute("src", this.getAttribute("src").replace("_off.", "_on."));  
                  }  
                  images[i].onmouseout = function() {  
                      this.setAttribute("src", this.getAttribute("src").replace("_on.", "_off."));  
                  }  
              }  
          }  
      }  
  }  
  if(window.addEventListener) {  
      window.addEventListener("load", smartRollover, false);  
  }  
  else if(window.attachEvent) {  
      window.attachEvent("onload", smartRollover);  
  }