How to display online/offline status by sitemap

Question

Hj all. I have a question that how to display online/offline status by sitemap.
I was able to Add or correct in sitemap but now I know know the way to display online/offline status by sitemap.I had this code :

<a href='ymsgr:sendIM?vietvoquoc&m= hello'><img border="0" src=http://opi.yahoo.com/online?u=vietvoquoc&t=5/></a></font>
but i haven't given it into sitemap yet. Anyone know the way to embed that code into a Node of sitemap.Hope reply.