unlock nokia E63

[romio77]

I have nokia E63, it is locked by 3-uk. Now i want to use another sim card which is not valid.
I tried to flash the phone with another product code values & flashed successfully with jaf tool...
the phone debranded but the sim lock still remains..
anyone could u help me to unlock the sim lock.
i could not understand that flashing phone deletes all the previous system and writes new or modifies some except simlock!!
Thanks in advance.