var js = 1.0;

Version = parseInt(navigator.appVersion);

if (navigator.appName == "Netscape")
    js = ((Version >= 4) ? 1.2 : ( (Version == 3) ? 1.1 : 1.0 ));
else
    if (navigator.appVersion.indexOf('MSIE') != -1) 
        js = ((Version >= 4) ? 1.1 : 1.0);

function changeImagemap(newImage) {
    if (js > 1.0) document ['main'].src = eval(newImage + ".src");
}

if (js > 1.0) {
    main = new Image();
    main.src  = "book_cover.gif";
	
	maini = new Image();
    maini.src  = "maini.gif";

    sectioni = new Image();
    sectioni.src  = "sectioni.gif";

    sectionii = new Image();
    sectionii.src  = "sectionii.gif";
	
	sectioniii = new Image();
    sectioniii.src  = "sectioniii.gif";

    sectioniv = new Image();
    sectioniv.src  = "sectioniv.gif";
	
	sectionv = new Image();
    sectionv.src  = "sectionv.gif";
}