Under the agreement, Vignette holders of outstanding shares will receive one additional share for every share they own on November 15.
The stock dividends resulting from the split are expected to be distributed December 1, 1999. Vignette common stock will begin trading on a split-adjusted basis December 2, 1999.
In February, shares in the software maker more than doubled on the company's first day of public trading.
Vignette, which makes publishing and personalization software for e-commerce and other large Web sites, and its existing shareholders raised $76 million in the IPO, which priced at $2 per share above the top of the expected $15 to $17 range set by lead underwriter Morgan Stanley Dean Witter.
At yesterday's close, Vignette's shares were up 6 points to 173.
CNET, publisher of News.com, is an investor in Vignette.