Connect your phone to xs++ 3.1 and copy your phones log without IMEI number here.

XS++ 3.1 Guide-Flashing, Customizing, Recovering

Global SonyEricsson Dictionary

You need to make a full flash first and then you can unlock it:

General Information about Patch-Unlocking (start here if you want to unlock)

Remove SIM-lock patch generator

Follow this tutorial step by step.

Have a nice day