Lexmark International ( LXK) Monday reported that second-quarter profit grew by a third, but issued cautious guidance because of what it called "the potential for aggressive price competition." The Lexington, Ky.-based printer maker posted a 34% increase in net income to $136.6 million, or $1.02 a share, vs. $101.7 million, or 72 cents a share, in the year-ago period and analysts' consensus estimate of 97 cents a share, according to Thomson First Call. Revenue rose 11% from a year ago to $1.248 billion. The company said gross profit rose to 35.3% of revenue vs. 34.0% a year ago. Lexmark forecast a year-over-year revenue growth rate of high single to low double digits and EPS of 90 cents to $1, vs. 79 cents a year ago. The consensus estimate was 97 cents. "We believe that our recent new product introductions and our business model position us well for continued growth," the company said. "We continue to be cautious, however, due to the uncertainty in the market and the potential for aggressive price competition." Shares fell $4.61, or 5%, to $88.36 in premarket trading.