//画像の先読み
if (document.images) {

	//menu1ボタン
	var menu1On = new Image();
	menu1On.src = "../common/menu1b.gif";
	var menu1Off = new Image();
	menu1Off.src = "../common/menu1a.gif";
	
	//menu2ボタン
	var menu2On = new Image();
	menu2On.src = "../common/menu2b.gif";
	var menu2Off = new Image();
	menu2Off.src = "../common/menu2a.gif";
	
	//menu3ボタン
	var menu3On = new Image();
	menu3On.src = "../common/menu3b.gif";
	var menu3Off = new Image();
	menu3Off.src = "../common/menu3a.gif";
	
	//menu4ボタン
	var menu4On = new Image();
	menu4On.src = "../common/menu4b.gif";
	var menu4Off = new Image();
	menu4Off.src = "../common/menu4a.gif";
	
	//menu5ボタン
	var menu5On = new Image();
	menu5On.src = "../common/menu5b.gif";
	var menu5Off = new Image();
	menu5Off.src = "../common/menu5a.gif";
	
	//menu6ボタン
	var menu6On = new Image();
	menu6On.src = "../common/menu6b.gif";
	var menu6Off = new Image();
	menu6Off.src = "../common/menu6a.gif";
}

//ロールオーバー
function rolloverOn(imgName) {
	if (document.images) {
		document.images[imgName].src = eval(imgName + "On.src");
	}
}

//マウスアウト
function rolloverOff(imgName) {
	if (document.images) {
		document.images[imgName].src = eval(imgName + "Off.src");
	}
}