Sony Ericsson Secret Menu:- 
-> * <- <- * <- *
  


(-> means press joystick, arrow keys or jogdial to the right and <- means left.)
You'll see phone model, software
info, IMEI, configuration info, sim lock status, REAL time clock, total call time and text labels.
You can also test your phones services and hardware from this menu (main display, camera, LED/ illumination, Flash LED, keyboard, earphone, speaker, microphone, radio and vibrator tests)