actually, you dont need to buy that key chain thingy. u can always buy the blizzard mobile authenticator. works on 99% of the phones in market except those phone that is not coloured screen. so why hassle to buy the keychain and pay for the dreadful cost of shipping when u can jus get the mobile authenticator for onli RM4? (its USD 0.99 if not mistaken) i am using one already and its running very well on my nokia 6300. if u dunno where to buy, go to this website :

mobile.blizzard.com