Android bluetooth link to Tata Indigo Manza Car

About one year back, I had purchased a TATA Indigo Manza Elan car. This has a feature to allow bluetooth based phone to connect to sound system in the car. This makes one handle hands-free phone call, while driving. I have a LG P500 Optimus Android based phone. Initially when I linked Bluetooth, it worked after I learned to connect the device. Some time back I upgraded my Android version to 2.3 from 2.2. After this I noticed that bluetooth link would connect but calls would not be handled properly. I could not hear incoming call etc.
I have been now able to solve this problem by adding an app named “Bluetooth Manager”, available from https://play.google.com/store/apps/details?id=com.mdsoftware.bluetoothpowermanager&hl=en. Now if I connect the car bluetooth system through this application, my phone call is handled properly. I do not know why it was not working otherwise but shared this here in case some one else has a similar problem.