Shares of Mercury Interactive ( MERQ) were down nearly 2% in after-hours trading after the company posted better-than-expected first quarter results but guided second-quarter earnings to the low end of analysts' estimates.The company said after the bell Thursday that net income in the first-quarter rose slightly to $18.9 million, or 21 cents a share from $18.1 million, or 21 cents a share, as new orders grew more than 30%. Excluding certain charges, amortization costs, and stock-based compensation (a non-GAAP basis), earnings rose to $23.8 million, or 24 cents a share, from $18.1 million, or 20 cents a share, a year earlier. On that basis, analysts had expected the company to earn 22 cents a share. For the second quarter, the business software maker said it expects to earn 9 cents to 16 cents a share on revenue of $160 million to $170 million. Mercury also expects new orders to grow 25% to 35% in the second quarter. On a non-GAAP basis, the company expects to earn 21 cents to 26 cents a share. A consensus analyst estimate was expecting 25 cents a share. Shares of Mercury were down 92 cents, or 2%, to $45.05 in after-hours trading after closing the regular session up 2.5%.