The Sensex opened with a positive gap of 138 points at 17,467. The index is now up 339 points at 17,668.All index stocks are in positive zone.Reliance Communications and Reliance Energy have surged nearly 3.5% each to Rs 633 and Rs 1,395, respectively.Infosys, ICICI Bank, SBI and NTPC have rallied 2% each to Rs 1,934, Rs 1,080, Rs 1,932 and Rs 210, respectively.Reliance has moved up 1.8% to Rs 2,330. Tata Steel, Satyam and TCS are the other major gainers.