Metavante Launches Triple DES Processing with Software from ACI Worldwide; ACI's New Transaction Security Services Technology Delivers Triple DES Processing Capabilities.

Business Editors/High-Tech Writers

OMAHA, Neb.--(BUSINESS WIRE)--April 3, 2003

ACI Worldwide (Nasdaq:TSAI), a leading international provider of enterprise e-payment solutions, today announced that Metavante Corporation, the financial technology subsidiary of Marshall & Ilsley Corporation, is using ACI's BASE24(R) Transaction Security Services software to provide Triple Data Encryption Standard (DES) processing services. Metavante is making the Triple DES services available to its EFT and Card solutions clients and has implemented Triple DES-capable ATMs for Peoples National Bank, Fairfield, Ill.

With the help of ACI's Security Optimization Service (SOS) consulting services, Metavante is ACI's first customer to add the new Transaction Security Services module to its BASE24 production environment to launch Triple DES processing services. Transaction Security Services is built on ACI's new multi-platform Enterprise Services software and manages all cryptographic functions, such as PIN verification, message authentication, chip authentication and card verification. The module provides an end-to-end Triple DES processing solution across the entire transaction path, including PIN encryption at ATMs, PIN verification during authorization, and encryption for switching to and from card networks.

Triple DES -- which replaces the current personal identification number (PIN) encryption standard -- triples the encryption algorithm used to protect PIN data. Its use was required by April 1, 2003, for MasterCard members and processor host systems and financial institutions that accept MasterCard or Cirrus transactions at any new, relocated or replaced ATM installed after April 1, 2002.

"When the mandate was announced, Metavante decided to make certain that the Triple DES capability was available to our clients before the published deadline," said Frank D'Angelo, executive vice president and general manager, Metavante EFT and Card solutions. "Our first step was to upgrade our platforms to support Triple DES processing. In partnership with ACI, we were able to add the necessary functionality to our BASE24 platform to support Triple DES at the ATM and with EFT networks. ACI provided the necessary software and expertise to help us reach our goal in advance of the Triple DES deadline."

ACI's Transaction Security Services combines support of Single and Triple DES, allowing customers to process in a mixed environment until card association and network mandates require them to completely adopt Triple DES. The module is certified with NCR, Diebold and Fujitsu brand ATMs, and supports hardware security devices from Thales e-Security, HP Atalla Security Products Group and Eracom Technologies.

"ACI is taking a leading role in providing new security services, and we're working hard to help our customers meet mandates and deadlines," said Mark Vipond, president of ACI Worldwide. "This has been a multi-year effort to develop solutions in support of Triple DES. We began shipping software last summer, and more than 150 customers are in the process of implementing various configurations of our solution. Metavante is a Triple DES pioneer, and we are pleased to have had the opportunity to help them launch their Triple DES capabilities."

Transaction Security Services is the foundation for all current and future cryptographic functionality within ACI software. It supports current industry PIN processing requirements as well as Europe's emerging chip standards, Canada's Interac requirements and Visa's unique key per ATM mandates. For more information, visit www.aciworldwide.com/3DES

About Metavante

To improve the financial experience for more than 5,100 clients - including the largest 20 banks in the United States - and their thousands of customers, Metavante(R) Corporation delivers virtually all of the technology that an organization needs to offer financial services. Metavante offers financial technology solutions that drive customer relationship management, electronic banking, electronic funds transfer and card solutions, electronic presentment and payment, financial technology services, and wealth management. Headquartered in Milwaukee, Wis., Metavante is wholly owned by Marshall & Ilsley Corporation (NYSE:MI). For more information see www.metavante.com.

About ACI Worldwide

Every second of every day, consumers are initiating electronic payment transactions -- getting cash at ATMs, using debit and credit cards to make purchases in stores and on the Internet, banking by phone and PC, paying bills online. Twenty seven billion times a year, ACI software is used to process these transactions, powering the world's online payment systems. ACI was founded in 1975 and pioneered the development of applications and networking software for online transaction processing. Today more than 520 customers in 71 countries use ACI supplied software. Visit ACI Worldwide on the Internet at www.aciworldwide.com.

Any statements in this press release regarding projected results are preliminary and "forward-looking statements" within the meaning of the Private Securities Litigation Reform Act of 1995. In addition, this press release may contain other forward-looking statements including statements regarding Transaction Systems Architects, Inc.'s ("TSA"), its subsidiaries or third parties' expectations, predictions, views, opportunities, plans, strategies, beliefs, and statements of similar effect. The forward-looking statements in this press release are subject to a variety of risks and uncertainties. Actual results could differ materially.

For a detailed discussion of these and other risk factors, interested parties should review TSA's filings with the Securities and Exchange Commission, including TSA's Form 10-K for the year ended September 30, 2002 (filed January 13, 2003) and Form 10-Q for the quarter ended December 31, 2002 (filed February 13, 2003).