Tumbleweed To Integrate Verisign's Payment Services With Secure Communications Platform To Enable Electronic Statement Presentment And Payment

Solution Combines Secure Online Statement Delivery with one-click Payment Purchasing

MOUNTAIN VIEW and REDWOOD CITY, CA - June 29, 2000 - Tumbleweed® Communications Corp. (Nasdaq:TMWD), a leading provider of advanced email solutions for business communications, and VeriSign, Inc. (NASDAQ:VRSN), a leading provider of Internet trust services, today announced that VeriSign's Payment Services will be integrated with Tumbleweed Integrated Messaging Exchange™ (IME™) secure communications platform to provide a complete solution for electronic statement presentment and payment. The companies expect the solution to be available to customers such as financial institutions, retailers, telecommunications and healthcare companies, in the third quarter of 2000. VeriSign and Tumbleweed also intend to collaborate on next-generation services such as digital receipts and solutions tailored to wireless networks.

Through the integration of VeriSign's Payflow Pro payment service with the IME platform, Tumbleweed will provide customers with the ability to deliver online statements to end-users and process corresponding payments with the ease and simplicity of "one-click". Tumbleweed IME is a platform and set of applications for creating secure communications channels between a business and its customers, partners, and suppliers. VeriSign's Payflow Pro service is a seamless payment processing solution that enables companies to authorize and manage credit card, debit card, purchase card, automated clearing house (ACH) and electronic check payments online.

"Electronic statement delivery is poised to enjoy phenomenal growth," said Jeffrey C. Smith, president and CEO, Tumbleweed Communications Corp. "We are pleased to work with VeriSign to deliver a powerful solution that will send millions of statements to customers who can pay over the Internet using virtually any type of payment device."

"As banks, brokerages, retailers and other service providers leverage electronic statement delivery to better serve their customers, the need for a trust infrastructure remains mission-critical," said Richard Yanowitch, executive vice president of worldwide marketing for VeriSign. "Through the combination of our Payment Services and Tumbleweed's IME, customers now have a highly scalable, secure communications platform that enables secure, anytime anywhere statement delivery and flexible online payment."

About VeriSign
VeriSign, Inc. (Nasdaq:VRSN) is the leading provider of Internet trust services - including domain name registration, authentication, payment, validation and network infrastructure services - to Web sites, enterprises, electronic commerce service providers and individuals, enabling trusted and secure electronic commerce and communications over the Internet. VeriSign's trust services for enterprises and electronic commerce service providers are available through regional account representatives, resellers, and VeriSign affiliates worldwide. The company's e-commerce services for Web sites, developers and individuals are available through www.verisign.com or through the company's Network Solutions subsidiary at www.networksolutions.com.

About Tumbleweed Communications Corp.
Tumbleweed is a leading provider of solutions for managing secure communication and collaboration to enable the business Internet. Tumbleweed's robust policy-based framework empowers organizations to safely share and protect critical information, increase customer loyalty and privacy and dramatically reduce costs. Tumbleweed is trusted by 1,000 blue-chip customers including American Express, Chevron, Datek Online, the European Union's Joint Research Council, First Union Wachovia, John Deere, Merrill Lynch, Nike, Northern Trust, NTT, Salomon Smith Barney, Travelers and US Food and Drug Administration. One hundred of the Fortune 500 are Tumbleweed customers. Tumbleweed Communications was founded in 1993 and is headquartered in Redwood City, Calif., with offices around the world.

Except for the historical information contained herein, the matters discussed in this press release may constitute forward-looking statements that involve risks and uncertainties that could cause actual results to differ materially from those projected, particularly with respect to the security features of Tumbleweed's products and the activities of any third party. In some cases, forward-looking statements can be identified by terminology such as "may," "will," "should," "potential," "continue," "expects," "anticipates," "intends," "plans," "believes," "estimates," and similar expressions. For further cautions about the risks of investing in Tumbleweed, we refer you to the documents Tumbleweed files from time to time with the Securities and Exchange Commission, particularly Tumbleweed's Form 10-K filed March 30, 2001 and Form 10-Q filed November 13, 2001. Tumbleweed assumes no obligation to update information contained in this press release.