No lawmakers were seen in T-shirts or sandals, but Capitol Hill was starting to resemble a Silicon Valley East yesterday.

A lineup of technology leaders addressed the congressional Joint Economic Committee, part of the JEC's National Summit of Technology, which will run through Wednesday. The first session featured a procession of lawmakers and executives -- and even Federal Reserve Chairman Alan Greenspan -- extolling the technology sector as the main driver of the booming U.S. economy.

"The most exciting news on the economic front has been the incredible advances that are being made in America's high-technology industries," said the JEC's chairman, Sen. Connie Mack (R-Fla.).

Greenspan told the panel that the U.S. economy "is displaying a remarkable run of economic growth that appears to have its roots in ongoing advances in technology."

With Wall Street listening anxiously for any hint whether the Fed many raise short-term interest rates at its next policymaking session at the end of the month, Greenspan stuck strictly to his technology text, and none of the legislators asked about monetary policy.

But the Fed chairman is likely to give financial markets a signal about his thinking at another JEC hearing Thursday, when his topic is specifically monetary policy and the state of the economy.

Greenspan said yesterday that innovations such as microprocessors, lasers, fiber-optic and satellite technologies have increased the efficiency of many types of production equipment, while innovations in information technology "have begun to alter the manner in which we do business and create value."

All this has helped raise the overall efficiency of the economy -- in particular, it has increased labor productivity -- and made it less inflation-prone, the Fed chairman said.

As he first did early last month in a speech in Chicago covering most the same themes, however, Greenspan cautioned: "The rate of growth of productivity cannot increase indefinitely. . . . Despite the remarkable progress witnessed to date, we have to be quite modest about our ability to project the future of technology and its implications for productivity . . . and for the broader economy."

International Business Machines Corp. chief executive Louis V. Gerstner Jr. led a lineup of industry leaders that included Intel Corp. chief executive Craig R. Barrett and former Netscape Communications Corp. chief James Barksdale. Microsoft Corp. Chairman Bill Gates is expected to address the committee today.

Gerstner admonished members against hastily passing laws to regulate the rapidly evolving technology world, saying that policies enacted today could be suddenly rendered obsolete. "It's a grave error to think the Internet and [electronic] business will develop under the kind of regulation we applied to the phone system back in the days when coal and steel were determinants of a nation's greatness," he said. "This means we have to be patient and thoughtful before rushing to enact new legislation."

Gerstner said the technology is being hurt badly by a shortage of skilled workers. There are 350,000 open jobs in the information technology industry today, Gerstner said, and he bemoaned "the deplorable condition of our system of public education."

Barrett, speaking by video hookup, backed a Senate bill that would limit awards in lawsuits over problems associated with the year 2000 computer problem, known as the Y2K issue. "Our main issue is that we not clog up the courts and tie down the industry with frivolous litigation," he said.

Opponents of the bill say it would stop consumers and small businesses from recovering losses associated with the date glitch.

In an interview, Sen. Robert F. Bennett (R-Utah), who chairs a special Senate committee on the Y2K issue, said he expects a vote on the bill as early as today. He said he expects 55 to 60 senators to vote in favor of the legislation.

Sen. Edward M. Kennedy (D-Mass.), a JEC member, said the bill will likely change significantly before it reaches its final version. "There are a number of innings left in this game," Kennedy said.

CAPTION: Among those at the Hill technology summit were, from left, James Barksdale, Louis Gerstner and Alan Greenspan.