userAgent = window.navigator.userAgent;
browserVers = parseInt(userAgent.charAt(userAgent.indexOf("/")+1),10);
function newImage(arg) {
    if (document.images) {
        rslt = new Image();
        rslt.src = arg;
        return rslt;
    }
}

function findElement(n,ly) {
    if (browserVers < 4)		return document[n];
    var curDoc = ly ? ly.document : document;
    var elem = curDoc[n];
    if (!elem) {
        for (var i=0;i<curDoc.layers.length;i++) {
            elem = findElement(n,curDoc.layers[i]);
            if (elem) return elem;
        }
    }
    return elem;
}

function changeImages() {
    if (document.images && (preloadFlag == true)) {
        var img;
        for (var i=0; i<changeImages.arguments.length; i+=2) {
            img = null;
            if (document.layers) { img = findElement(changeImages.arguments[i],0); }
            else { img = document.images[changeImages.arguments[i]]; }
            if (img) { img.src = changeImages.arguments[i+1]; }
        }
    }
}

var preloadFlag = false;
function preloadImages() {
    if (document.images) {
        choix_over = newImage("images2009/choix-over.png");
        bulletin_over = newImage("images2009/bulletin-over.png");
        resultats_over = newImage("images2009/resultats-over.png");
        preloadFlag = true;
    }
}