Is it licensed?
If bitcoin is not considered as a currency / security, do you need a licence?
It could be considered as an e-marketplace, where people just buy and sell an asset.
I have been in-conversation regarding this matter with Tax Consultants. As you mentioned above its not considered a currency. And as per current laws if there is no law on a matter the law of India will be followed. Since there is currently no Law in India on the matter we stand the same. The Reserve Bank Of India has cautioned people to be careful on investing in bitcoins. We might go ahead and register as a company in the e-marketplace.
Bitcoin being an asset is one thing, but this type of business means you'll be holding (fiat) money on behalf of your customers (and also their assets - BTC). So it's a bit more than just selling bitcoins online.
Have you consider enquiring directly to the relevant authority, just to be on the safe side?