Rising rupee is not just a matter of concern for India's exporters but it is a challenge for policy makers too. And they now want to choke out what they see as not the most needed source of dollar flows into the country.So the PM's economic think-tank has a message for corporate India and its hunger for cheap overseas debt-tighten your belt. Last fiscal India Inc raised over $16 billion as ECB proceeds, so far in this fiscal the figure has already crossed $21 billion and is growing.