NEW YORK (Reuters) - Accenture Ltd., the world's largest consulting firm, yesterday said quarterly earnings rose 15 percent as lower tax rates and a weak U.S. dollar offset a shift to lower-margin back-office operations.

Officials of the Bermuda-based company also said the company had uncovered potential violations of US laws against corrupt business practices in its Middle East operations.

Accenture said it expected the probe to have no material affect on its finances and said it had volunteered what it knew to US government agencies. A US Department of Justice spokesman had no comment.

The quarterly earnings topped estimates, trumping fears by some analysts that Accenture might miss Wall Street expectations and driving Accenture's shares 7 percent higher.

"Investors were nervous they were even going to make the number," said Richard Davis, an analyst with Needham & Co. "Some people thought the company might report earnings as low as 22 cents," said Davis, who rates the stock a "buy."

The company said net income for the third quarter ended May 31 rose to $132.1 million, or 28 cents per share, from $114.5 million, or 27 cents, a year earlier. The number of shares outstanding increased in the latest quarter.

Earnings were boosted by an unexpected one-time reduction in the corporate tax rate, which lifted profits by 2 cents per share.

The company in April had forecast profit of 24 cents to 26 cents per share. Estimates by analysts had averaged 25 cents per share, according to Reuters Research, a unit of Reuters Group Plc.

Shares of Accenture rose $1.31 to $20.16 on the New York Stock Exchange in afternoon trade.

The company generates revenue from a mix of consulting and computer services. Accenture is the fifth largest computer services supplier.

Accenture has been at the vanguard of a global movement by companies to turn over back-office operations such as payroll processing and customer service to contractors such as Accenture, which is seeking to replace falling demand for its traditional technology consulting work by corporate clients.

Net revenues rose 2 percent to $3.04 billion from $2.98 billion.

Revenues were at the top end of the range it forecast in April, boosted by the benefit of the weak dollar, which increases the value of overseas earnings when they are converted into dollars. Excluding the impact of currency exchange, revenue would have fallen 5 percent.

Looking ahead, the company said it expected earnings in the fourth quarter ending August 31 seasonally its weakest quarter in a range of 21 cents to 25 cents per share and for net revenues to grow between 5 percent and 10 percent.

Analysts surveyed by Reuters Research expected, on average, for Accenture to post fourth-quarter profits around 24 cents.

"We are not counting on the market to hand as much in terms of demand improvement for the remainder of this year," Accenture Chairman and Chief Executive Joe Forehand said during an investor conference call following the report.

Chief financial officer Harry You said the company was planning for earnings of around $1.10 per share for the fiscal year ending in August 2004, but that would vary due to the effects of potential accounting change mandates.

Consulting new bookings grew modestly and represented 42 percent of the $5.2 billion in overall new bookings during the third quarter. But consulting revenue dropped 8 percent in the period. Outsourcing accounted for $944 million, or 31 percent of net revenue.

Gross margins fell to 36.3 percent from 41.2 percent a year earlier, partly reflecting higher upfront costs of business in the first year of new outsourcing contracts, the company said.