DULLES, Va. (AP) -- Second-quarter earnings for America Online Inc. nearly quadrupled as the nation's largest online service handily beat Wall Street expectations.

AOL said Wednesday that it earned $121 million, or 22 cents per share, compared with $33 million, or 6 cents per share, for the same quarter in 1997.Revenue was up 62 percent to $960 million, compared with $592 million last year. In the three-month period ended Dec. 31, AOL added 1.6 million customers.

The company's stock jumped 4 percent, or $6.50, to $172 in morning trading Thursday on the New York Stock Stock Exchange.

The net earnings figures include an accounting adjustment that allowed the company to deduct past losses from its tax bill, which raised net income.

Not including the adjustment, AOL earned $88 million, or 17 cents per share. That was well above expectations of analysts surveyed by First Call Corp. who had predicted AOL would earn 14 cents a share.

AOL, which has more than 15 million subscribers, plus 2 million with its subsidiary CompuServe, is planning to buy Netscape Communications Corp. for $4.2 billion in a deal expected to close this spring. The Netscape browser site draws 20 million visitors each month.

"In 1998, the Internet truly came of age and became even more integral to people's everyday lives," said Steve Case, chairman and chief executive officer. "We're excited about the opportunities presented by our pending combination with Netscape as well as our alliance with Sun Microsystems to drive the growth of this new medium."

During the quarter, the company launched AOL in Australia in a joint venture with Bertelsmann AG and announced a joint venture with the Cisneros Group to develop and market AOL services for Latin America.

Revenues from customers' online fees grew 61 percent to $779 million. Revenues from advertising and online transactions rose 66 percent to $181 million.

In the six months ended Dec. 31, earnings rose 356 percent to $228 million, or 41 cents per share, from $64 million, or 13 cents per share, in the last half of 1997.

Revenues grew to $1.8 billion from $1.1 billion.

The company also announced Wednesday a 2-for-1 stock split to take effect on Feb. 22. It is the sixth split since the company went public in March 1992. The most recent split was Nov. 17.