update Android provider.Settings.System value

Question

it seen i can't write to settings in LG-P500 (Android 2.2). This is my code: android.provider.Settings.System.putInt(getContentResolver(), android.provider.Settings.System.AUTO_TIME, 1);

Value to specify if the user prefers the date, time and time zone to be automatically fetched from the network (NITZ). 1=yes, 0=no

It work fine in my emulator android 2.2 I also try in other phone, HTC android 2.1 it works fine too.

Could anyone know what would be the problem? Thank you very much.