Business Editors & Technology Writers

OMAHA, Neb.--(BUSINESS WIRE)--April 24, 2002

ACI Worldwide (Nasdaq:TSAI), a leading international provider of enterprise e-payment solutions, announces a significant increase in the performance of its WINPAY24(TM) payment processing application operating on IBM eServer Intel-based systems. The results of benchmark testing indicate that WINPAY24 is capable of supporting up to 500 transactions per second (TPS) -- a level of performance previously achievable only on mainframes.

WINPAY24 is a feature-rich electronic fund transfer (EFT) processing application used by 29 retailers in the United States and Mexico to authorize and route credit, debit, gift, phone and loyalty card transactions; refunds; checks; and electronic benefits transfer (EBT) transactions.

Benchmark testing of WINPAY24 was conducted at IBM's Solution Center in Waltham, Massachusetts, using a group of five IBM eServer xSeries servers running Microsoft(R) Windows 2000(R) Server and Microsoft SQL Server 2000 Enterprise Edition database systems, and a distributed application model. The tests simulated a workload of 500 locations generating a mix of credit, debit, EBT and check requests for authorization. WINPAY24 generated an average response time of .336 seconds for internal processing, topping the previous benchmark by 10 times. That is equivalent to processing 1,800,000 payment transactions per hour. Additional results show that with adequate hardware, WINPAY24 can support substantial volume up to 500 TPS.

"The benchmark clearly demonstrates WINPAY24's ability to handle the large, centralized databases and high transaction volumes encountered in today's online retail environment," said Charles Linberg, ACI's chief technical officer. "This is great news for our retailers that rely upon WINPAY24 and IBM eServer xSeries for cost-effective, mission-critical EFT processing."

An IBM eServer x370 system was used as the database server in the benchmark testing, configured with eight 550-MHz Intel Pentium III Xeon processors and 4 gigabytes of memory. CPU utilization averaged 60 percent. Four IBM eServer x320 systems, each with two 1.13GHz Intel Pentium III Xeon processors and 2 gigabytes of memory, were also used in the testing. Average CPU utilization on the application servers was 81 percent.

"The results show that WINPAY24, combined with the mainframe-inspired features of IBM eServer xSeries systems, can provide the power to meet the online EFT processing throughput requirements of the most demanding retailer," said Doug Oathout, director of IBM eServer xSeries marketing.

WINPAY24 recently received ClusterProven status from IBM. The ClusterProven validation indicates that the solution has availability and scalability characteristics beyond those achieved on a single server node to help maintain application availability in the event of a failure.

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 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 540 customers in 71 countries use ACI supplied software. Visit ACI Worldwide on the Internet at www.aciworldwide.com.

The IBM eServer brand consists of the established IBM e-business logo with the descriptive term "server" following it. IBM, the e-business logo, xSeries and ClusterProven are trademarks of IBM Corporation in the United States and/or other countries.

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. Factors that could cause actual results to differ include but are not limited to the following.

TSA's business is concentrated in the banking industry, making it susceptible to a downturn in that industry.

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