Hello everyone,
I purchased the code from CellUnlocker, after paying, I get the code after some hours, I enter at the prompt UNLOCK windows after enter PIN of SIM, just enter 1 time and my phone can unlock immediately.
Perfect...!
I was working for 3 day with a lot of software without result.
Now, no matter if I want to use official ROM from T-Mobile (USA) - I am living in Germany - or custom ROM from CyanogenMod, my S4 never ask me again unlock code.
I am happy with this result.