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Siebel Systems
www.siebel.com

SAN MATEO, CA., June 19, 2002 - Siebel Systems, Inc. (Nasdaq: SEBL), the world's leading provider of eBusiness applications, today announced that Západočeská Energetika A.S. (ZCE), one of the Czech Republic's leading energy companies, has standardized on Siebel eEnergy 7, a comprehensive suite of eBusiness applications that enables energy service providers to manage sales, marketing, and customer service across all communication channels and points of customer contact. ZCE is using the software's prebuilt, tailored functionality to develop a complete 360-degree understanding of its customers. It will use this enhanced customer and market insight to improve its quality of customer care, increase customer loyalty, maximize sales effectiveness, and streamline partner management.

ZCE is transforming its business operations in anticipation of the energy market liberalization in the Czech Republic. To strengthen its position in the electricity market, the company has introduced a new brand-NOVÁ ENERGIE-to provide customers with high-quality, price-competitive energy products and services. Through its Siebel eEnergy 7 implementation, the company united its customer, product, and billing information to effectively understand and satisfy customer needs. Prior to its Siebel Systems deployment, ZCE faced a major challenge in integrating numerous, fragmented customer information silos.

Working in collaboration with Siebel Consulting Partner and systems integration specialist Soluziona, ZCE is implementing Siebel eEnergy 7 Sales, Siebel eEnergy 7 Call Center, Siebel eEnergy 7 Service, Siebel eEnergy 7 PRM, and Siebel eEnergy 7 eCustomer. This powerful blend of Siebel eEnergy 7 modules enables the company to develop a single, unified view of its customers across multiple channels, including the Internet, face-to-face contact, the telephone, and its network of service delivery partners.

ZCE will use its comprehensive customer insight to effectively manage customer acquisition, retention, and churn management; streamline the management of complex sales contracts; and effectively capture, validate, and manage accurate service orders. The Siebel solution supports ZCE's complex service account and billing hierarchies, and it delivers efficient management of and collaboration with the company's national network of service partners. Siebel Systems' interactive, zero-footprint Web-based application also accelerates integration with ZCE's bespoke billing and back office systems to deliver competitive advantage through rapid service activation at a dramatically lower risk. Siebel eBusiness Applications will provide the flexible front office capabilities needed to expand ZCE's product offerings in the increasingly competitive market.

"To remain competitive in the new open market for energy solutions in the Czech Republic, ZCE must strive to deliver reliable, first-class service at a competitive price," says Miroslav Kucera, Director of Customer Care, ZCE. "Using the industry-tailored functionality of Siebel eEnergy 7, ZCE is rapidly emerging as an efficient, customer-centric organization, focused on effective customer acquisition, service, and retention."

ZCE is one of the Czech Republic's leading energy companies. It generates, distributes, and markets power supplies to 500,000 customers in the Plzeň and Karlovy Vary regions of the country and manages seven percent of the total market for electricity supplies in the Czech Republic.

About Siebel Systems
Siebel Systems, Inc. is the world's leading provider of eBusiness applications software. Siebel Systems provides an integrated family of eBusiness applications software, enabling multichannel sales, marketing, and customer service systems to be deployed over the Web, in call centers, in the field, through reseller channels, and across retail and dealer networks. Siebel Systems' sales and service facilities are located in more than 32 countries. For more information, please visit Siebel Systems' Web site at www.siebel.com.

Except for the historical information contained herein, this press release contains forward-looking statements that involve risk or uncertainties. Future operating results of Siebel Systems may differ from the results discussed or forecasted in the forward-looking statements due to factors that include, but are not limited to, risks associated with customer relations, such as the availability of Siebel Systems' products and services, customer implementation of products and services, relationships with customers, third-party vendors and systems integrators, concentration of revenues in a relatively small number of customers, existence of errors or defects in products, ability to successfully manage growth, significant current and expected additional competition and the need to continue to expand product distribution and services offerings. Further information on potential factors that could affect the financial results of Siebel Systems are included in Siebel Systems' Annual Report on Form 10-K, Quarterly Reports on Form 10-Q and its other filings with the Securities and Exchange Commission, which are available at www.sec.gov. Siebel Systems assumes no obligation to update the information in this press release.

Siebel is a trademark of Siebel Systems, Inc. and may be registered in certain jurisdictions. All other product and company names mentioned are the property of their respective owners and are mentioned for identification purposes only.

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