Code
<script>
var usersonline = document.all['uonline'].innerHTML;
if(usersonline.indexOf("vip") > -1)
usersonline = usersonline.replace('vip','<font color="red">vip</font> <img src="http://www.coolz.ucoz.ru/sml/369.gif">');
document.all['uonline'].innerHTML = usersonline;
</script>