function popup(url, fenetre, largeur, hauteur) {
    var coordY  = ( screen.height - hauteur ) / 2;
    var coordX  = ( screen.width - largeur ) / 2;
    window.open( url, fenetre, "top=" + coordY + ", left=" + coordX + ", width=" + largeur + ", height=" + hauteur + ", status=no, resizable=yes, location=no, directories=no, scrollbars=yes");
}

function popupUnique ( url, fenetre ) {
	popup(url, fenetre, 600, 500);
}