The Sensex at the Bombay Stock Exchange rose 121 points, or 0.7 per cent, to 17,829 in early trade, this morning, on continued buying by funds and retail investors, amid a mixed trend in the other Asian markets. But the Sensex later trimmed its initial gains, to stand a more modest 78 points, or 0.4 percent in positive territory, at 17,785 in afternoon deals, a short while ago. The Sensex has already gained more than 840 points in the last five trading sessions.Other Asian markets in Japan, China, Hong Kong, South Korea, Taiwan, and Singapore were trading mixed, today, as renewed fears of a debt default by Greece gave pause to mounting hopes that the global economy is improving