Sony: Official Bootloader Unlocked XPERIA phones
The opportunity to unlock would be provided in this spring for certain releases of XPERIA 2011 phones.
Sony Ericsson has been listening to Android community and that is why they have decoded to open up in a secure manner. Phones, such as Xperia arc, Xperia neo, Xperia pro and Xperia PLAY would be unlockable for developers. However, not all phones will get it. Sony would allow it to happen only for certain releases of the phones. For example, you can’t unlock the boot loader if you have a SIM lock protected phone.Generic rule of the thumb is to connect your phone to the Fastboot tool in the Android SDK and see if your phone can connect to Fastboot, the boot loader can be unlocked. XPERIA X10 will not get this privilege.
If you unlock the boot loader and then flash a custom unsigned ROM to your phone, the custom unsigned ROM will not have gone through the thorough tests that we run for each phone and software version that we release. Because of that, the custom unsigned ROM might not work properly on your phone. Certain functions may cease to work, and the performance of the device might not be ideal.
How to Enable Official Bootloader Unlock
To enable this, Sony would be launching a web service where an unlock boot loader key can be retrieved by entering your IMEI. This key will be used in Fastboot where you perform the actual unlock boot loader sequence. No software updates would be required for this. More on this soon.