function MM_preloadImages() { //v3.0
  var d=document; if(d.images){ if(!d.MM_p) d.MM_p=new Array();
    var i,j=d.MM_p.length,a=MM_preloadImages.arguments; for(i=0; i<a.length; i++)
    if (a[i].indexOf("#")!=0){ d.MM_p[j]=new Image; d.MM_p[j++].src=a[i];}}
}

function preload() {
    var imageStack = new Array('images/heart1.gif',
                               'images/heart2.gif',
                               'images/heart3.gif',
                               'images/heart4.gif',
                               'images/heart5.gif');
                               
    for(i=0; i<imageStack.length; i++){
        MM_preloadImages(imageStack[i]);
    }
}