I got this from the web but i havent tried them on my phone,If theres someone tried them or knows they can work let me know.............


*#3370# - Enhanced Full Rate Codec (EFR) activation. Increase signal strength, better signal reception. It also help if u want to use GPRS and the service is not responding or too slow. Phone battery will drain faster though.
*#3370* - (EFR) deactivation. Phone will automatically restart. Increase battery life by 30% because phone receives less signal from network.

Chao................

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