is this in Indian context?
will latest RCDMA SIM works in GSM phones straight away? i dont think so
Removable User Identity Module (R-UIM) is a card developed for cdmaOne/CDMA2000 ("CDMA") handsets that extends the GSM SIMcard to CDMA phones and networks. To work in CDMA networks, the R-UIM contains an early version of the CSIM application. The card also contains SIM (GSM) application, so it can work on both networks. It is physically compatible with GSM SIMs and can fit into existing GSM phones as it is an extension of the GSM 11.11 standard QUOTED THIS FROM WIKI.. DONT KNOW IF IT APPLIES IN INDIA ALSO, BUT THIS IS WHAT THEY SAY RUIM IS ..