I have been visiting nokia customer care centre subsequently from last 7 days...But now it seems that those people are unable to resolve the problem. As they say, my handset is unable to catch "vodafone" network, which seems very unrealistic to me, as they are saying, that, it will never be able to catch vodafone signals from now onwards.
On these grounds when i asked them to fix this as soon as possible, they intimated me that, if they try to fix it up then this will no longer receive any network.