//ロールオーバー
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);	 
}