Wincor Nixdorf deploys ACI software for transaction processing

Wincor Leverages BASE24-es to Drive End-to-End ATM Service

(Watford, England – 13 December 2006) – ACI Worldwide (Nasdaq: TSAI), a leading international provider of enterprise payments solutions, today announced that Wincor Nixdorf has implemented ACI’s BASE24-es® software as a transaction processing system for its end-to-end ATM service.

The new service includes an ATM helpdesk, maintenance, cash and settlement operation and transaction processing. One of the world’s leading providers of IT solutions to retailers and retail banks, Wincor Nixdorf intends to expand the offering to license its managed ATM services across Europe.

BASE24-es is the industry-leading integrated payment engine for acquiring, authenticating, routing, switching and authorising financial transactions. The SEPA-ready solution is also EMV, PCI and TDES compliant – delivering a complete solution for the European market.

Wincor Nixdorf is using the software to provide a comprehensive authorisation process. ACI is also providing ongoing maintenance and support services.

John Ennis, director, banking division in the UK at Wincor Nixdorf, said, “ACI has provided us with a truly world class authorisation and authentication system. The system has enabled us to create a flexible processing platform to greatly enhance our comprehensive ATM service. We are confident the software will help us provide an efficient and cost-effective transaction service for the banking and retail markets.”

Richard Launder, group executive, ACI Worldwide EMEA said, “We realised the importance of well-managed ATM systems for businesses and have developed functionality within our BASE24-es software that combines excellence of service with the most up-to-date technology. We also realised outsourcing the management of the system would provide benefits to Wincor including the ability to deliver an end-to-end service for banking and retail clients resulting in opportunities for cost savings and improved efficiency.”

About Wincor Nixdorf

Wincor Nixdorf is one of the world’s leading suppliers of IT solutions to banks (private client banking) and retailers. The company’s extensive portfolio, consisting of hardware products, software, consulting, maintenance and other services, is aimed at reducing the cost and complexity of business processes within branch operations at the same time as improving service to the customer.

The company has about 7000 employees and made net sales of € 1,744 million last fiscal year. Wincor Nixdorf has a presence in over 90 countries and has its own subsidiaries in 31 of these. In terms of dispatches of automated teller machines (in-house estimates) and dispatches of programmable “ePOS” electronic point-of-sale units (source: Clarendon Report, April 2004), Wincor Nixdorf is one of the three leading suppliers worldwide. We also hold the Number 1 position in Europe in programmable ePOS systems, as measured by dispatch volumes. The main production facilities are at corporate head office in Paderborn, Germany, and in Singapore.

About ACI Worldwide

Every second of every day, ACI solutions are at work processing electronic payments, managing risk, automating back office systems and providing application infrastructure services. Founded in 1975, ACI is a leading international provider of solutions for consumer and wholesale banking, retail and cross-industry systems. ACI serves over 800 customers in 83 countries including many of the world's largest financial institutions, retailers and payment processors. 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 the Company's filings with the Securities and Exchange Commission, including the Company’s Form 10-K filed on December 14, 2005, the Company’s Form 10Q filed on February 9, 2006, the Company’s Form 10Q filed on May 10, 2006, and the Company’s Form 10Q filed on August 9, 2006.

Published on: 12:00AM on 13th December 2006