CONTACT INFORMATION

Peace Software
www.peace.com

MIAMI, FL., July 25, 2001 – Peace Software, a leading provider of advanced customer management solutions for utilities and retail energy companies, and Rational Software® (Nasdaq: RATL), the e-development company, today announced that Peace Software has deployed Rational software configuration tools to further scale its development center to support its expanding and broadening customer base in regulated, transitional and competitive energy markets.

"Rational's advanced e-development platform further scales and accelerates our development processes, reinforcing our lead in the market with innovative new generation technology in our advanced Energy suite of software," said Paul Grey, Executive Vice President of Technology at Peace Software. "As a result, our clients receive regular new releases of Energy that provide them the latest features, technologies and efficiencies."

Chris Galloway, Country Manager for Rational Software New Zealand, said, "Rational tools are behind many of the world's largest and most profitable software companies. As leading software companies like Peace scale their development organizations to meet demand, our tools ensure that their expanding development teams continue to work in unison for optimum performance."

Peace's 200-strong development center is entirely dedicated to developing energy customer management solutions. The company's development teams use Rational ClearCase® and Rational ClearQuest® to work collaboratively together, to design, build and test Energy enhancements and innovations on time and on budget. Peace's upcoming Energy Version 7 release is being developed using Rational tools and will ship at the end of 2001.

About Peace Software
Peace Software, Inc. delivers the most comprehensive and cost-effective customer management solutions for utility and retail energy companies. Peace Software's industry-leading Energy suite is being rapidly deployed in 30 U.S. and international energy markets. Based on open industry standards, the innovative and customer-proven Energy suite integrates customer and commodity management for commercial and industrial (C&I) and mass markets. Headquartered in Miami and founded in 1984, Peace Software is a global company with offices in the United States, Canada, Australia and New Zealand. Visit us at: www.peace.com

About Rational Software Corporation
Rational Software provides a platform for software development which speeds time-to-market while improving software quality. This integrated, full life-cycle solution combines software engineering best practices, market-leading tools, and professional services. Ninety of the Fortune 100 and 49 of the Fortune e-50 build software with the Rational solution. This open platform is extended by hundreds of partners providing more than 500 complementary products and services. IDC has recognized Rational as the revenue leader in multiple application development and deployment markets for four years in a row. Founded in 1981, Rational, one of the world's largest software companies, had revenues of $815 million in its fiscal year ended March, 2001 and employs more than 3,700 people around the world. Rational is a component of the Nasdaq-100 Index®. Additional information is available on the Internet at: www.rational.com

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