Did you but it at mobihand.com? If you did, log in to your account there and you have the option to change/update your PIN, which will re-generate a serial for you.
If you have a copy or your reciept I would forward it to BBsmart saying that you got a new BB with the following pin if they could send you a new code.
I've done this every time I got a new berry and they always gave me the cde within 1 or 2 business days. their email is [email protected]