// "constants"

//browser = (((navigator.appName == "Netscape") && (parseInt(navigator.appVersion) >= 3 )) || ((navigator.appName == "Microsoft Internet Explorer") && (parseInt(navigator.appVersion) >= 4 )))

nav1 = new Image();
nav1.src = "nav1.gif";
nav1_on = new Image();
nav1_on.src = "nav1_on.gif";

nav2 = new Image();
nav2.src = "nav2.gif";
nav2_on = new Image();
nav2_on.src = "nav2_on.gif";

nav3 = new Image();
nav3.src = "nav3.gif";
nav3_on = new Image();
nav3_on.src = "nav3_on.gif";

nav4 = new Image();
nav4.src = "nav4.gif";
nav4_on = new Image();
nav4_on.src = "nav4_on.gif";

nav5 = new Image();
nav5.src = "nav5.gif";
nav5_on = new Image();
nav5_on.src = "nav5_on.gif";

nav6 = new Image();
nav6.src = "nav6.gif";
nav6_on = new Image();
nav6_on.src = "nav6_on.gif";

nav7 = new Image();
nav7.src = "nav7.gif";
nav7_on = new Image();
nav7_on.src = "nav7_on.gif";

nav8 = new Image();
nav8.src = "nav8.gif";
nav8_on = new Image();
nav8_on.src = "nav8_on.gif";

function addbutton(imgname) {
        eval(imgname + ' = new Image()');
        eval(imgname + '.src = "images/" + imgname + ".gif"');
        eval(imgname + '_on = new Image()');
        eval(imgname + '_on.src = "images/" + imgname + "_on.gif"');
}

// event handler functions
function msover(imgname) {
        if (document.images) document.images[imgname].src = eval(imgname + '_on.src');
}
function msout(imgname) {
        if (document.images) document.images[imgname].src = eval(imgname + '.src');
}