function setEventHandler(widget) {
    // preload the -over image
    var x = new Image;
    x.src = 'images/' + widget + '-over.gif';
    // get the image widget from the document
    var wd=document.getElementById(widget);
    if(wd.src==x.src) {
    // if it's already set to -over, forget it
        return;
    }
    // otherwise add listeners to handle mouseovers and mouseouts
    wd.onmouseover = function() {
        wd.src = 'images/' + widget + '-over.gif';
    }
    wd.onmouseout = function() {
        wd.src = 'images/' + widget + '.gif';
    }
}

function preloadImages() {
    // preload and set event handlers for each image
    setEventHandler('apply');
    setEventHandler('program');
    setEventHandler('dates');
    setEventHandler('contact');
    setEventHandler('roadmap');
    setEventHandler('loan');
    setEventHandler('meetings');
}