Your browser can't handle XMLHttpRequest. This will only work in IE 5/6, Mozilla, Firefox, Safari and Opera 8. This page is still accessible though. The links just aren't checked.
The next list has some links to websites.
check.php source (horrible proof of concept, please improve ;)<?php
header('Content-Type: text/plain;charset=utf-8');
$status = (@gethostbyname($_GET['uri']) ? 'okay' : 'broken');
?>document.getElementsByTagName('a')[<?php echo $_GET['link']; ?>].className = '<?php echo $status; ?>';
if (<?php echo $_GET['link']; ?> < (linksMax - 1)) {
checkLink(<?php echo $_GET['link']; ?> + 1);
}