if(document.images) {
pics = new Array(); 
pics[1] = new Image();
pics[1].src = "http://www.kreawereld.nl/img/leesverder_normal.gif"; 
pics[2] = new Image();
pics[2].src = "http://www.kreawereld.nl/img/leesverder_hover.gif";
}

function changer(from,to) {
if(document.images) {
document.images[from].src = pics[to].src;
}
}