There was a case/scam about 2 years ago where a person was selling Kingfisher tickets through an email and mobile phone in Mumbai.

1) This guy was advertising in local papers/it cafes etc
2) You ask him for a ticket
3) he quotes 50% less than what airline are selling.
4) he purchases it with a stolen credit card.
5) you pay 50% in cash to him
6) he pockets the cash and you fly

Kingfisher were targetted big time and that is why there website can be a bit anal with foreign credit cards.

Also the reserve bank of India stated that cards without verified by visa or securecard codes will not be able to use online bookings. fair play to them to try and cut down fraud.