Imate sp5

first switch off ur phone and then do following

here it is
1. Press and hold soft1 and soft2 keys.
2. Press and hold power button for around 1 to 1.5 seconds. Release power button. Keep hold soft1 and soft2 keys.
3. Later, screen shoould show instructions to ask user to press '0' key to reset to factory default.
4. Press '0' within the timeout period, which is only several seconds only.
5. If no instruction is shown on the screen, repeat steps 1 to 4.
The timing is sensitive.

but you will loose all data.

pls rate me fixya if i have fixed what u needed