PHP and MySQL Full Text Search Problem

Hi all, My first try at MySQL Full Text Search and it is not behaving ;) Here is what I have for my query string: $sql = "SELECT id, concat(fname, ' ', lname, ' ', degree1) as name".

       " FROM tbl_personnel WHERE MATCH (fname,lname) AGAINST ('" .
       $attributes['searchstring'] . "')";

This works pretty good. The only problem is it only works if there is an exact match for either the first name (fname) or last name. For example. In tbl_personnel there are 5 people with the first name Christine. If I pass Chris to this query in $attributes['searchstring'] I get 0 results. If I pass Christine I get all 5. What do I need to modify to make this work? Thanks, Charles