if (document.images) {

img1on = new Image(); //On Images
img1on.src = "graphics/BG_WebMontage.jpg";
img2on = new Image();      
img2on.src = "graphics/BG_WebMontage.jpg";



img1off = new Image(); //Off Images
img1off.src = "graphics/BG_Site.gif";
img2off = new Image(); 
img2off.src = "graphics/BG_Site.gif";


}

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

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