How did you get on with this? I'm doing the same thing in a month? 10 months agoAnswered by Phil via WorldNomads.com
Technically, as long as you're not stepping outside the terminal, you don't need a visa. You'll have to stay in the transit area and you'll need to be holding a confirmed onward ticket.
In case you want to get the visa.....
http://www.immihelp.com/nri/indiavisa/transit-visa-india.html 10 months ago