function failsafeImg(){
var badImg = new Image();
badImg.src = 'images/www_error.jpg';
for(var i=0;i<document.images.length;i++){
var cpyImg = new Image();
cpyImg.src = document.images[i].src;
if(!cpyImg.width){
document.images[i].src = badImg.src;
}
}
}
onload = failsafeImg;