Hidden Iframe - Div

I'm using the following script to trasfer content from a hidden Iframe to a div.

function loadExternal(url) {
if ( window.frames['buffer'] ) {
window.frames['buffer'].location = url;
var lyr = document.getElementById? document.getElementById('display'): document.all? document.all['display']: null;
if ( lyr && typeof lyr.innerHTML != "undefined" ) {
lyr.innerHTML = '<img src="ld.gif" alt="">'
}
return false;
}
return true;
}

function displayExternal() {
var lyr = document.getElementById? document.getElementById('display'): document.all? document.all['display']: null;
if ( window.frames['buffer'] && lyr && typeof lyr.innerHTML != "undefined" ) {
lyr.innerHTML = window.frames['buffer'].document.body.innerHTML;
}
}

It works ok and brings up the linked pages but the images on the pages will not show. The pages are in sub folders along with all the images that pertain to it. Im just confused here, Why does the script load the pages but will not the display any of the corresponding images?