Bayan Telecommunications Maximizes Interconnection Efficiency with Portal Software; Successfully reduced costs and enabled faster time to market with new services.

Business Editors/High-Tech Writers

CUPERTINO, Calif.--(BUSINESS WIRE)--Dec. 16, 2003

Portal Software, Inc. (Nasdaq:PRSF) and Bayan Telecommunications (BayanTel), a leading Philippines-based telecommunications service provider, today announced that BayanTel has successfully completed implementation of Portal's billing solution.

The deployment of Portal's flexible multi-carrier billing solution was achieved in a very short time frame, allowing BayanTel to maximize interconnect revenue. Portal's complete solution for interconnection billing provides details for interconnect events, enabling BayanTel to verify interconnect costs and maximize the value of it's interconnect business.

"In the past decade, we have moved from a market where the dominant influence was monopolistic to one where it is fiercely competitive," said Tunde Fafunwa, BayanTel chief consultant. "At BayanTel, we recognize the increasing customer demands for new services that must be delivered more quickly and cheaply. This has made the need for seamless connection greater than ever.

"Portal's billing platform provides us with a complete set of tools to maximize interconnection carrier settlement efficiency, supplying reliable, comprehensive information for precise control of interconnection traffic."

"Interconnect charges can account for a significant portion of a telecommunications service provider's operating cost as well as generate significant revenues for operators. In a competitive environment, the negotiation of interconnect agreements is a skilled and vitally important function; and the billing and verification of interconnect charges are now key business processes," said David Yuen, vice president and general manager, Portal Software Asia Pacific. "BayanTel's success in the marketplace hinges on its customer focus and we are delighted that Portal is able to provide the basis for BayanTel to be nimble in an increasingly competitive environment where all aspects of interconnection activities can be processed and monitored."

About Portal Software, Inc.

Portal Software provides flexible billing and subscriber management solutions to enable organizations to monetize their voice and digital transactions. Portal's convergent billing platform enables service providers to charge, bill, and manage a wide range of services via multiple networks, payment models, pricing plans, and value chains. Portal's flexible and scalable product-based solutions enable customers to introduce new value added services quickly, providing maximum business value and lower total cost of ownership. Portal's customers include thirty-five of the top fifty wireless carriers as well as organizations such as Vodafone, AOL Time Warner, Deutsche Telekom, TELUS, NTT, China Telecom, Reuters, Telstra, China Mobile, Telenor Mobil, and France Telecom. For more information, please visit www.portal.com.

About Bayan Telecommunications, Inc.

Bayan Telecommunications (BayanTel) is a facilities-based, fixed-line telecommunications and data services provider, offering a full range of switched and dedicated local exchange services. BayanTel provides national and international long distance services to residential, business and carrier customers in the Philippines. In data communication services, BayanTel is recognized as the leading provider in the domestic data market. Find out more about BayanTel at http://www.bayantel.com.ph.

Note to Editors: Infranet and the Portal logo are U.S. registered trademarks, and Portal is a trademark of Portal Software, Inc. All other trademarks are the property of their respective owners. All statements made in this press release are made only as of the date set forth at the beginning of this release. Portal undertakes no obligation to update the information in the event facts or circumstances subsequently change.