function preload(imgObj,imgSrc) {
	if (document.images) {
		eval(imgObj+' = new Image()')
		eval(imgObj+'.src = "'+imgSrc+'"')
	}
}

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");
    }
  }
}

//preload
preload("global_products_on", "/i/global_products_on.gif");
preload("global_products_off", "/i/global_products_off.gif");
preload("global_cap_on", "/i/global_cap_on.gif");
preload("global_cap_off", "/i/global_cap_off.gif");
preload("global_corporate_on", "/i/global_corporate_on.gif");
preload("global_corporate_off", "/i/global_corporate_off.gif");