Caterpillar Inc reported a higher-than-expected quarterly profit and raised its 2011 sales forecast, sending its shares to an all-time high, as rising commodity prices increased mining industry demand for its earth-moving equipment.

The company also sounded an upbeat note on the outlook for the global economy, including the United States and Europe, which have lagged emerging markets in the recovery.

One measure of Caterpillar's growing confidence: it is hiring again. The company, which cut nearly 30,000 full-time and contract jobs worldwide during the recession, said it rehired about 8,200 full-time workers in 2010 -- two-thirds of them outside the United States.

In addition, the company said it had hired another 11,000 contract workers -- about half of them in the United States.

Caterpillar also forecast it would post a 2011 profit near $6.00 per share, slightly above the market consensus of $5.86, according to Thomson Reuters I/B/E/S. It also said 2011 revenue would be more than $50 billion, up from an earlier forecast that it would approach $50 billion.

We feel good, Doug Oberhelman, the company's chairman and chief executive, said in statement. The outlook reflects our expectation that the world economy will continue to recover.

Caterpillar also benefited from lower taxes, including the renewal of the research and development tax credit. The company's shares were up 1 percent in late morning at $96.69 after hitting an all-time high at $97.79.

The past two years have been whiplash-inducing for the Peoria, Illinois-based company. In 2009, Caterpillar's sales tumbled 37 percent to $32.4 billion, triggering the worldwide layoffs. In 2010, they snapped back 31 percent to $42.6 billion.

Caterpillar said higher coal and metals prices were lifting machine sales in nearly every part of the globe, including North America, where sales more than doubled in the most recent quarter.

On balance, the company benefits from higher commodity prices because the increased demand from miners more than offsets the added material costs it pays.

Caterpillar reported fourth-quarter net profit of $968 million, or $1.47 a share, up from $232 million, or 36 cents a share, a year earlier.

Sales at the company, which also makes diesel engines, gas turbines and railroad locomotives, rose 62 percent during the quarter to $12.8 billion.

Analysts on average had expected the company to earn $1.27 a share on sales of $11.63 billion, according to Thomson Reuters I/B/E/S.

Caterpillar said its order backlog stood at $18.7 billion at the end of 2010, nearly double what it was at the end of 2009.

Demand continues to be especially strong for mining equipment, the company said, with customers having to wait between eight and 18 months for delivery.

The volumes are terrific, said Eli Lustgarten, an analyst at Longbow Securities.

But Alex Blanton, an analyst at Clear Harbor Asset Management, called the company's margins disappointing.

During a conference call to discuss the results, Mike DeWalt, Caterpillar's head of investor relations, said that was a result of a very negative shift in sales mix with the company selling more lower-margin machines and engines.

DeWalt added: Over the past quarter we have become somewhat more positive about economic growth in the developed economies of North America, Europe, and Japan.

Caterpillar said it expected the U.S. economy to grow about 3.5 percent in 2011, which it said would be the best rate since 2004. It expects China, which has contributed mightily to its profitability in recent years, to grow 9.5 percent in 2011.

(Reporting by James B. Kelleher; Editing by Derek Caney and Matthew Lewis)