if (document.images) {     

image0on = new Image(); image0on.src = "images/index/Button_deutsch_highlight.gif"; 
image1on = new Image(); image1on.src = "images/index/Button_englisch_highlight.gif"; 

image0off = new Image(); image0off.src = "images/index/Button_deutsch_normal.gif"; 
image1off = new Image(); image1off.src = "images/index/Button_englisch_normal.gif"; 

}
function turnOn(imageName) {
if (document.images) {
document[imageName].src = eval(imageName + "on.src");
}
}
function turnOff(imageName) {
if (document.images) {
document[imageName].src = eval(imageName + "off.src");
}
}