Apple reported strong earnings growth for its second fiscal quarter, hauling in profit of $1.05 billion—a 36 percent increase—on $7.51 billion in revenue, thanks to robust Mac and iPod sales.

Despite strong second-quarter numbers, Apple shares were down as much as 6 percent in after-hours trading because the company's third-quarter earnings forecast of $1 per share missed analysts' estimate of $1.10.

The strong second-quarter numbers were powered by booming sales of Mac computers, with some 2.29 million units sold, easily beating Wall Street's consensus estimate of 2 million. Mac unit sales jumped 51 percent over the same period one year ago.

IPod sales were also strong, Apple said, with 10.6 million units sold, beating analyst estimates of 10 million. IPhone sales were right around the Street's prediction of 1.7 million.

"We're delighted to report 43 percent revenue growth and the strongest March quarter revenue and earnings in Apple's history," said Steve Jobs, the company's chief executive. "With over $17 billion in revenue for the first half of our fiscal year, we have strong momentum to launch some terrific new products in the coming quarters."

Last quarter, Apple reported revenue of $9.6 billion, a number which reflects its seasonally strong performance during the holidays, when it sells the most iPods, iPhones, and computers. For its third fiscal quarter, Apple forecast $7.2 billion revenue, slightly above the $7.15 billion Street consensus.

Last quarter, Apple reported revenue of $9.6 billion, a number which reflects Apple's seasonally strong performance over the holidays, when it sells the most iPods, iPhones, and computers. For its third fiscal quarter, Apple forecast $7.2 billion revenue, slightly above the $7.15 billion Street consensus.

During a conference call with analysts and reporters, Apple chief financial officer Peter Oppenheimer said the company remains confident in reaching its stated goal of selling 10 million iPhones by the end 2008.

"We are very pleased with iPhone momentum and we remain confident of achieving our goal of selling 10 million iPhones in calendar 2008," Oppenheimer said.

Oppenheimer said Apple intends to release the next generation of iPhone software—dubbed iPhone 2.0—in late June.

Apple's strong earnings numbers come on the same day the company announced that it had purchased chipmaker P.A. Semi Inc. for about $270 million, giving Apple a toe-hold in the microprocessor market.

The move confused some Apple watchers, because P.A. Semi's chip technology is based on I.B.M.'s Power PC technology, which Apple abandoned years ago in favor of Intel chips, which are better suited to mobile devices, analyst Nathan Brookwood told the Wall Street Journal.

Brookwood said that while the deal may not make sense now, it could very well pay dividends in the future.

"You're an amateur, and you don't understand and then, 20 moves later, it becomes clear why they did it," Brookwood said.

During the conference call, Apple officials declined to comment on the "purpose or plans" of its P.A. Semi purchase.