Hitachi netBusiness Announces New Se-nD. Com Service

REDWOOD CITY, CA - July 6, 2001 - Tumbleweed® Communications Corp. (Nasdaq:TMWD), a leading provider of mission-critical messaging software, announced today that Hitachi netBusiness Ltd. has adopted Tumbleweed Integrated Messaging Exchange™(IME™) for its new Secure Contents Delivery service called Se-nD.com. Hitachi netBusiness is a provider of net business platforms for Internet businesses and offers services ranging from ASP, Data Center (hardware and middleware), business process outsourcing and consulting. Hitachi netBusiness plans to launch its Se-nD.com service in July 2001.

Tumbleweed IME is an enterprise software suite that leverages the Internet and existing email infrastructure to enable customized secure online communications. It is used to create secure business messaging channels between an enterprise and its customers, partners and suppliers and used to deliver content securely over the Internet. Tumbleweed Communications KK is the Japanese subsidiary of Tumbleweed that has been working with Hitachi netBusiness to adopt IME 4.0J, the localized Japanese version of IME.

The new service being offered by Hitachi netBusiness leverages the functionality of email's "push" and the Web's "pull" and is designed to provide a highly secure, trackable and encrypted communications channel for businesses to communicate with financial and business partners, public organizations and customers. Se-nD.com service automatically encrypts and delivers messages over the Internet to anyone with an email address and a Web browser with no need to install additional software or train end-users.

Hitachi netBusiness's service Se-nD.com will facilitate a secure communications channel between the sender and the receiver of messages that allows for secure exchange of content such as contracts and administrative forms. Se-nD.com leverages the broad reach of the Internet while adding security, reliability, scalability and management features that are base requirements for any business messaging platform.

About Hitachi netBusiness
Hitachi netBusiness, Ltd. offers services to businesses that range from ASP, Data Center (hardware and middleware), business process consulting, and outsourcing. Hitachi netBusiness' mission is to provide their online customers with outstanding service and secure communications functionalities that meet their multiple needs as a business. More information on Hitachi netBusiness can be found at http://www.hi-nb.com/english/

About Tumbleweed
Tumbleweed Communications Corp. (NASDAQ: TMWD) is a leading provider of mission critical messaging software that enables organizations to manage and secure online business communications and processes. Tumbleweed's customers use the company's solutions to define secure communication networks, to centrally control and monitor the corporate communications stream and to create a foundation for automated preparation and secure Internet delivery of sensitive business information. Companies that rely on Tumbleweed Communications solutions include American Express, Chase Manhattan Bank, Chevron, Datek Online, the European Union's Joint Research Council, FDA, John Deere, Merrill Lynch, Nike, Northern Trust, NTT, Salomon Smith Barney, Travelers, United Parcel Service, and seven of the world's largest postal services. Tumbleweed Communications was founded in 1993 and is headquartered in Redwood City, CA. More information can be found at www.tumbleweed.com.

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.