I don't know how accurate this information is.
http://www.nucpros.com/?q=node/5288Indian Crew For Cursed Russian Boat
Strategy Page
November 9, 2008: Despite Russian and Indian officials refusing to verify long rumored Indian leasing of a Russian nuclear submarine, more information continues coming out that the deal is very much on. Last December, Indian officials seemed to acknowledge that it is leasing at least one Russian Akula II SSN (nuclear attack submarine), which will enter Indian service in 2009. That sub is currently undergoing trials in the Pacific ocean. These are going well, after two weeks, except for the accidental activation of the fire extinguisher system, which killed twenty sailors and civilians, and injured more than twenty. There were 208 people aboard the sub at the time, most of them navy and shipyard personnel there to closely monitor all aspects of the sub as it made its first dives and other maneuvers.
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India also expects to complete construction of its own nuclear sub design in a year or two, and begin sea trials and tests. This boat is based on Russian technology, but is basically Indian designed and built. The Russian Akula will basically serve as a training boat for India's new nuclear submarine force.
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Once the ATV SSN is proven, a modified version will be built as a SSBN (ballistic missile carrying sub). This was how everyone else did it, including the Chinese. Get an SSN operational, then modify the design to include some SLBM launch tubes.