Join Date:Joined: May 2011
If you go into 'settings' then 'about phone' you will see the phones baseband version. If it ends in 15 it is most likely one of the two firmwares you mention. If you try to install a rom dependant on these firmwares and you don't have it you will temporarily brick your phone. (Requiring the use of the Sony Ericcson Update Service to hopefully restore the phone to working order).
It is possible your phone has the firmware already installed but you need to check! Some network providers have been very slow at releasing them. If you manage to find the firmware on the web (make sure it is the correct language and layout for your locale - AND the correct phone) then you need to use a flashing utility to install it, I use 'flashtool' as it can root the phone and install xrecovery, but you must be sure you read the documentation and follow the proceedure.
Once you have xrecovery and the phone is rooted the magic can begin..
Be careful. Its very easy to render your phone bricked (as in the phone is as useful as a brick!). No one here can take responsibility for the advice given or your actions.
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