i can only help u if i know ur problem, u have only stated that ur phone is blocked but u have not stated in which way e.g is ur phone asking for a PUK code or for a PIN code.
THEN i CAN help U,wot U will have to do is put anuda o2 sim card in ur phone and ring the o2 provider and they will give u the code for ur uda sim and it won't even cost u a peeny.
I hope u resolve ur problem, in future if any help is needed i'd be glad to be of assistance
shahbaan786@hotmail.co.uk
SLick, February 2008