Finally i got an Siemens C45 mobile phone. when i got it , it was also kind of dead (not functioning well) so i took the PCB and after some cleaning and heat up the fella works fine. I did some changers to the SIM socket location and wired the battery points. Today i tested the battery charging part and it also works fine.
Have to make a small circuit for charging part and DTMF decoding part. The interesting part will be the serial connection between micro controller and the phone by which it can be controlled.