function rolloverImg() {
	var imgBuff = new Array();
	var imgElement = document.getElementsByTagName('img');
		
	for(var i=0; i<imgElement.length; i++){
		if(imgElement[i].className == 'imgover'){
			var src = imgElement[i].src;
			var ftype = src.substring(src.lastIndexOf("."), src.length);
			var hsrc = src.replace(ftype, '_over'+ftype);
			
			imgElement[i].src_rollout = src;
			imgElement[i].src_rollover = hsrc;
			
			imgElement[i].onmouseover = function() { this.src =  this.src_rollover; }
			imgElement[i].onmouseout = function() { this.src =  this.src_rollout; }
			
			imgBuff[i] = new Image();
			imgBuff[i].src = hsrc;
		}
	}
}

try{
	window.addEventListener("load",rolloverImg,false);
}catch(e){
	window.attachEvent("onload",rolloverImg);
}