Hi to all!, i want to share this usefull info with you. When you do a GSM registration and your using r74 or r74a firmware version you probably get the +CREG:x,1, (well of course you can ask for it if you send the at+creg? command), in that precise moment your are registered to the gsm net. Thats not news!, but when the CPU changes the gsm CELL you recieve another +CREG:x,1, this means that you have a new CELL but still registered!, you dont have to register again. Its a common mistake trying to re-register the gsm service when the CPU has this behaviour.
Well, that was all!.