A short online search yielded the following unlock steps. I tried it, and now my Samsung speaks Hebrew (well, not really - but it uses my Cellcom SIM card without a hitch ).
Caution: the following steps may cause actual damage to your phone. I do not recommend them, nor do I assume any responsibility in case you suffer any damage. Follow these steps only if you know what you're doing.
And thanks to Falcon1975, whoever you are, for originally posting these steps.
- Turn the phone off, take out AT&T SIM card and insert one from a different carrier. Turn the phone on.
- At the WRONG CARD screen type on the keypad:
(wait 10-15 seconds - the phone will restart on its own)
- When phone completes reboot type:
*7465625*638*00000000*00000000#(these are groups of 8 zeros)
- Next type:
#7465625*638*00000000#(again, 8 zeros)
- Then type
*#7465625#to check the locks.
All locks should now be inactive:
network lock - inactive
subset lock - inactive
sp lock - inactive
cp lock - inactive
sim lock - inactive
activa lock - inactive
phone lock - inactive
auto network - inactive
auto subset lock - inactive
auto sp lock - inactive
auto cp lock - inactive
- That's it! Your phone is now SIM, Voice and Data unlocked. Take it to a trip around the world. Phones deserve to have fun too .