browserName = navigator.appName;
	browserVer = parseInt(navigator.appVersion);
	if ((browserName == "Netscape" && browserVer >= 3) | (browserVer >=4)) version ="yes";
		else version = "no";

	if (version == "yes") {
		btn4_1on = new Image(15, 142);
		btn4_1on.src = "./images/btn4_1b.gif";
		btn4_2on = new Image(15, 142);
		btn4_2on.src = "./images/btn4_2b.gif";
		btn4_3on = new Image(15, 142);
		btn4_3on.src = "./images/btn4_3b.gif";
		btn4_4on = new Image(15, 142);
		btn4_4on.src = "./images/btn4_4b.gif";
		btn4_5on = new Image(15, 142);
		btn4_5on.src = "./images/btn4_5b.gif";
		btn4_6on = new Image(15, 142);
		btn4_6on.src = "./images/btn4_6b.gif";
		btn4_7on = new Image(15, 142);
		btn4_7on.src = "./images/btn4_7b.gif";
		btn4_8on = new Image(15, 142);
		btn4_8on.src = "./images/btn4_8b.gif";

		btn4_1off = new Image(15, 142);
		btn4_1off.src = "./images/btn4_1a.gif";
		btn4_2off = new Image(15, 142);
		btn4_2off.src = "./images/btn4_2a.gif";
		btn4_3off = new Image(15, 142);
		btn4_3off.src = "./images/btn4_3a.gif";
		btn4_4off = new Image(15, 142);
		btn4_4off.src = "./images/btn4_4a.gif";
		btn4_5off = new Image(15, 142);
		btn4_5off.src = "./images/btn4_5a.gif";
		btn4_6off = new Image(15, 142);
		btn4_6off.src = "./images/btn4_6a.gif";
		btn4_7off = new Image(15, 142);
		btn4_7off.src = "./images/btn4_7a.gif";
		btn4_8off = new Image(15, 142);
		btn4_8off.src = "./images/btn4_8a.gif";
	}

	function img_act(imgName) {
		if (version == "yes") {
			imgOn = eval(imgName + "on.src");
			document [imgName].src = imgOn;
		}
	}

	function img_inact(imgName) {
		if (version == "yes") {
			imgOff = eval(imgName + "off.src");
			document [imgName].src = imgOff;
		}
	}