function addLoadEvent(func) {
    var oldonload = window.onload;
    if (typeof window.onload != 'function') {
        window.onload = func;
    } else {
        window.onload = function() {
            if (oldonload) {
                oldonload();
            }
            func();
        }
    }
}

if (document.images) {

 prcdon = new Image();
 prcdon.src = "/images/prcd_logo_on.gif";

 prcdoff = new Image();
 prcdoff.src = "/images/prcd_logo_off.gif";

 rolloffon = new Image();
 rolloffon.src = "/images/rolloff_logo_on.gif";

 rolloffoff = new Image();
 rolloffoff.src = "/images/rolloff_logo_off.gif";

 }