At the stock markets, after a positive opening, the Sensex at the Bombay Stock Exchange remained firm, and had jumped 219 points, or 0(point)7 percent, to 30,521, a short while ago.The Nifty at the National Stock Exchange had climbed 68 points, to 9,429.And at the forex market, the rupee had strengthened a good 21 paise, to 64.52 against the dollar in afternoon deals.