Returning lock status to Blackberry Pearl

[Zoombaman]

My main phone is a Dash and I have a 6030 as a backup. Recently I was given a used Blackberry Pearl that has been unlocked AND the software (firmware) is an older version (4.2.0.42). I have downloaded the 4.2.1.107 update and plan to install it. I would actually like to return the phone to T-Mobile locked status.

Question: If I load this new firmware update, will it re-lock the phone to T-Mobile? Again, this is what I want because my experience has been that the functionality of locked phones is better in terms of how phone programs and features will work. Just to be clear, I received the phone in a T-Mobile retail box and it was originally a T-Mobile phone.

[Ellen]

Zoombaman I could be wrong here, but as far as I know the lock status on GSM handsets has nothing to do with the software that is programed into it. Doing an update to your phone will only upgrade the software that is programed into it, but would not re-lock the handset.....Once a phone has been unlocked, I don't think it can be relocked again.

[Zoombaman]

I just flashed the new OS version but the phone is still unlocked. It doesn't appear that I am losing any T-Mobile functionality so that's OK. Thanks!