function getAppVersion() {
		appname= navigator.appName;
		appversion = navigator.appVersion;
		majorver = appversion.substring(0, 1); 
		if ( (appname == "Netscape") && ( majorver >= 3 ) ) return 1;
		if ( (appname == "Microsoft Internet Explorer") && (majorver >= 4) ) return 1;
        return 0;
}

function swtch(num, imgname) {
        if (getAppVersion())
                imgname.src = img[num].src;
}
imgsrc = new Array();
imgsrc[0]  = "images/but1.gif";
imgsrc[1]  = "images/but1a.gif";
imgsrc[2]  = "images/but1.gif";
imgsrc[3]  = "images/but1b.gif";
imgsrc[4]  = "images/but1.gif";
imgsrc[5]  = "images/but1c.gif";
imgsrc[6]  = "images/but1.gif";
imgsrc[7]  = "images/but1d.gif";
imgsrc[8]  = "images/but1.gif";
imgsrc[9]  = "images/but1e.gif";
imgsrc[10]  = "images/but2.gif";
imgsrc[11]  = "images/but2a.gif";
imgsrc[12]  = "images/but2.gif";
imgsrc[13]  = "images/but2b.gif";
imgsrc[14]  = "images/but2.gif";
imgsrc[15]  = "images/but2c.gif";
imgsrc[16]  = "images/but2.gif";
imgsrc[17]  = "images/but2d.gif";
imgsrc[18]  = "images/but2.gif";
imgsrc[19]  = "images/but2e.gif";
imgsrc[20]  = "images/but2.gif";
imgsrc[21]  = "images/but2f.gif";
imgsrc[22]  = "images/but2.gif";
imgsrc[23]  = "images/but2g.gif";
imgsrc[24]  = "images/but2.gif";
imgsrc[25]  = "images/but2h.gif";
imgsrc[26]  = "images/but2.gif";
imgsrc[27]  = "images/but2i.gif";

if (getAppVersion()) {
        img = new Array();
        for (i = 0; i < imgsrc.length; i++) {
                img[i] = new Image();
                img[i].src = imgsrc[i];
        }
}