Add this to your Headers if you don't have it already. If you already have it, don't add it:
<script src="jquery.js"></script>
Footers:
<script>
function addText_toMiniProfile(){
$(function(){
//Created by Agent Moose (smcodes.smfforfree3.com)
var addText = new Array()
addText[addText.length] = ["USERNAME","TEXT/HTML"]
if(location.href.match(/topic/i)){
for(v=0;v<addText.length;v++){
$("td b a:contains(addText[v][0])").after("<br>"+addText[v][1]);
};};});}
addText_toMiniProfile();
</script>
USERNAME = Place the Username of the person to add the text/html to.
TEXT/HTML = The Text or HTML that wil show in the usere mini-profile. Remember, use Single Quotes ('), Not Double (").
Enjoy
