Erasing all its initial gains, the Sensex at the Bombay Stock Exchange stood 87 points, or 0.5 percent in negative territory, at 17,899, in afternoon trade, a short while ago. Earlier in the morning, however, the Sensex had gained 79 points, at 18,065, on bargain-hunting by investors, in beaten down stocks. Other markets in Japan, China, Indonesia, Hong Kong, Singapore, South Korea and Taiwan were down by between 0.1 percent and 0.7 percent, as investors kept a keen eye on the debt problems of Greece.