Código PHP:
$reg_query = sprintf("INSERT INTO users (username,mail,userpass,rank,staff,birth,sex,points,confirmed,conf_code) values ('%s','%s','%s','Usuario','Usuario','%s','%s','0','0','%s')",
mysql_real_escape_string($username),
mysql_real_escape_string($email),
mysql_real_escape_string($pass),
mysql_real_escape_string($age),
mysql_real_escape_string($sex),
mysql_real_escape_string($conf_url));