kindly read again the 1st post...its basically switching...but with some advancement and features compared to older dual sim module...and it works with 3G phones.
this does not make your ordinary phone DUAL ACTIVE...it just adds DUAL SIM function...
there is a diffence...however receiving calls from both networks is also possible...
its menu driven...no more *#7370#...no more rebooting with nokia phones...adds convenience...