you need to download a program called NSS

http://www.b-phreaks.co.uk/index.php?main_page=page_2

and then follow one of the guides which shows how to change product code ( very easy)

get dojj to give you the product code from his handset (on a sticker under battery) as stus phone was a generic phone to start with

simply change code and then do a software update using the std nokia software

job done

or if your near coventry i can do it as a favour for ya