Yes u misunderstood ...
I meant this :
Suppose u got a site : example.com
Post your HTML ( Motd) there .. ex : - example.com/motd.html
Now add this to motd.txt ( server side )
HTML Code:
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="refresh" content="0;URL=http://example.com/motd.html">
</head>
<body>
</body>
</html>
Now with this meta refresh .. client's MOTD will surely refresh contents from your site (example.com ) to his motd and will surely work ... as i have my MOTD on my site with html + CSS and it works