thanks it's better now, at least i can make and receive calls.
however, i have some problem with messaging.
for certain people, i have no problem but for some others, no matter how many times i try, the message stays in the outbox labelled as "failed"
the reason for the failure is 'invalid phone or message centre number. check the number.'
please help, i dun want to only be able to send messages to half the people in my contacts. =(