hi i've got a sony k610i trying to unlock it from 3.

i think i know what i need to do... its currently on cid52 and i think i need to get a firmware file, and then use the generator program to generate a vkp file which i patch using se tools to my phone in order to unlock it.

my question though, i've found the page of firmware files, theres 10 or so of them but which one do i use? does it matter?