if (document.images) {

image1on = new Image();
image1on.src = "gfx/but-home-hi.jpg";
image1off = new Image();
image1off.src = "gfx/but-home.jpg";

image2on = new Image();
image2on.src = "gfx/but-nieuws-hi.jpg";
image2off = new Image();
image2off.src = "gfx/but-nieuws.jpg";

image3on = new Image();
image3on.src = "gfx/but-voorstellingen-hi.jpg";
image3off = new Image();
image3off.src = "gfx/but-voorstellingen.jpg";

image4on = new Image();
image4on.src = "gfx/but-contact-hi.jpg";
image4off = new Image();
image4off.src = "gfx/but-contact.jpg";

image5on = new Image();
image5on.src = "gfx/but-links-hi.jpg";
image5off = new Image();
image5off.src = "gfx/but-links.jpg";

image6on = new Image();
image6on.src = "gfx/but-archief-hi.jpg";
image6off = new Image();
image6off.src = "gfx/but-archief.jpg";
} 

function changeImages() {
if (document.images) {
for (var i=0; i<changeImages.arguments.length; i+=2) {
document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
}}} 

function PopupPic(sPicURL) { 
  window.open("popup.html?"+sPicURL, "",  "location=no,status=no,menubar=no,scrollbars=no,resizable=no,height=300,width=300"); 
}