First i tried debranding my S500i with a S500i firmware, then i proceeded to use this instruction: http://www.topsony.com/forum/showthread.php?t=6329
in order to unlock it. YES IT WENT SUCCESSFULLY BABY
But still phone doesn't work with other carrier...lame??

So i flashed it to W580i using this guide:
HowardForums: Your Mobile Phone Community Debranding with SETool 2 Lite

THEN i used the guide above: Remove SIM-lock patch generator using the w580i firmware in order to unlock it. Now i am not sure if this is ok (i wanted to try w580i) but the process went smoothly. Everything was done correctly. (Write Script worked in the end as well)

But phone is still locked (is there a way to check if phone is really locked/unlocked)
Any ideas on what might be the problem here?