there is no one code
what u can do is take it to a sony ericsson service centre and get them to flash the phone and update the software, if u specificly ask them to remove the bar they can
shouldnt cost much either

I have a T68i, and its standard service provider is orange, but i would like to change the service provider to T-Mobile. I tried entering the T-Mobile SIM card but the screen read ' Insert correct SIM card' is there any special code to make the phone accept the T-Mobile SIM card. I think i have to unlock the phone but i cannot find any code for this. Does anyone out there know this code??