Hello guys, did u install NITDroid and connect to Internet via Network Provider? Coz I am having difficulty connecting to Internet via TATA Docomo (Primary Phone No.)?

I have tested with the following networks so far :
i) TATA Docomo (2G) : Shows "No Service", NET & SMS Not Working, if I try calling.. I get the "No-SIM or No-Service" error
ii) Vodaphone (2G) : NET Worked (Friend's SIM), SMS Works, Calling Works (But den no Voice)
iii) !dea (3G) : NET doesn't work, SMS Works, Calling Works (No Voice) (Office No.)

I don't wanna change TATA Docomo No., have a nice thing going on with it (long hours chit-chat.. etc)

So any Help?