SAN FRANCISCO -- The

Securities and Exchange Commission

Friday announced a three-month extension for companies to comply with recently issued guidelines on revenue recognition that have raised concerns about the accounting practices of some high-tech firms.

Publicly traded companies with fiscal years beginning between Dec. 16, 1999 and March 15 now will have the option of complying with the guidelines, known as Staff Accounting Bulletin No. 101, or SAB 101, beginning in the second quarter instead of the first, as was originally ordered.

In a statement, the SEC said its staff had "received requests from a number of groups asking for additional time to study" SAB 101. The agency didn't have a figure for how many firms contacted it regarding the issue, said spokesman John Heine.

SAB 101 was originally issued on Dec. 3 but didn't really register in Wall Street's consciousness until this week. On

Monday, shares of

MicroStrategy

(MSTR) - Get Report

stumbled 61% to 86 3/4 after the Internet software developer said it would restate its results for 1999 and 1998 to comply with SAB 101.

The Vienna, Va.-based company said it would spread recognition of revenue from some software sales with service contracts over the life of the contracts. This will defer revenue for some complex contracts. The company had previously split its revenue into software and services components, recognizing a good portion of the revenue up front.

The stock fell another 15.9% to 72 5/16 Tuesday before recovering the final three days of the week. Friday, the shares rose 10.7% to 129.

MicroStrategy's decline set off a mini "who's next" panic in the investment community and concerns that the approaching first-quarter earnings season could be blotted by similar restatements.

"The big problem is it's difficult from publicly available information to determine who might be impacted," said Janet Pegg, an accounting analyst at

Bear Stearns

. "You need a full understanding of a company's business practices and how they mesh with revenue recognition policies."

As for the SEC's decision to extend the date for compliance with SAB 101, "I don't know the SEC's thinking," Pegg said. "There are a lot of companies

potentially affected, but the SEC knew that in December."