The Sensex has sneaked into the positive zone for a brief while, but soon slipped back into negative zone. The index is now down 21 points at 10,488.Gujarat Ambuja (GACL) has soared over 4% to Rs 96.15. ACC has rallied 3% to Rs 735.Dr.Reddy's has surged 2.6% to Rs 1,337. Infosys, Satyam, NTPC, SBI and ICICI Bank are the other smart gainers among the Sensex stocks.Ranbaxy is down 3.4% at Rs 417. Bharti Tele has declined 3.2% to Rs 379.Maruti, Hero Honda and Tata Motors have dropped over 2% each to Rs 861, Rs 880 and Rs 859, respectively.BHEL, HDFC, Hindalclo and Cipla are the other prominent losers among the Sensex stocks. Out of 2,524 stocks traded so far, 1,508 have declined, 938 have advanced and the balance are unchanged.