Thanks a lot Pankaj
you can use cdma handsets from abroad(800mhz only) on Tata, Bsnl(Tarang) and Mtnl(Garuda) network,u just have to program the cdma channels to whichever network u want to use it.
For Tata u need to load Tata's prl on the handset to use it while roaming,whereas Bsnl and Mtnl dont offer roaming on their cdma networks so no prl is required for them.For Tata u just have to program it and load a gsk available in the market,whereas for Mtnl and Bsnl u have to program it and give them the esn no to have it updated on their database.Unfortunately Reliance does not allow other handsets even from other Indian networks,so forget using handsets from abroad on Reliance network.