// preload navigation images:

        if (document.images) {

		back_on = new Image();
                back_on.src = "images/backon.gif";
                back_off = new Image();
                back_off.src = "images/backoff.gif";
                
		online_on = new Image();
		online_on.src = "images/online_on.gif";
		online_off = new Image();
		online_off.src = "images/online_off.gif";

		download_on = new Image();
		download_on.src = "images/download_on.gif";
		download_off = new Image();
		download_off.src = "images/download_off.gif";
		
		tariff_on = new Image();
		tariff_on.src = "images/tariff_on.gif";
		tariff_off = new Image();
		tariff_off.src = "images/tariff_off.gif";          
                
}
                        
function hiLite(imgID,changeID) {
                        
        if (document.images) {
        document.images[imgID].src = eval(changeID + ".src");
        return true;
        }
}