Business/Technology Editors

    STAMFORD CT/REDWOOD CITY CA--(BUSINESS WIRE)--Sept. 8, 1999--

    - Improved, Secure Internet-based Messaging System
    Powered By Tumbleweed IME(TM) Technology

    Pitney Bowes (NYSE:PBI) Mailing Systems and Tumbleweed Communications Corp. (NASDAQ:TMWD) today announced that Pitney Bowes iSend(SM) On-line Document Delivery System has been significantly enhanced and will be distributed through several new marketing channels nationally. iSend, based on Tumbleweed's Integrated Messaging Exchange(TM) (IME(TM)), enables businesses to securely send and track the electronic delivery of any file to anyone with e-mail access.

"Pitney Bowes is widely recognized as a mail and messaging management leader. Our customers expect us to offer leading edge technology. This latest release of the iSend(SM) System, powered by Tumbleweed's IME technology, enables us to provide even greater levels of functionality, security and tracking of on-line communications," states Judy Martin, Vice President Strategic Marketing, Pitney Bowes Mailing Systems. "And, we're also making this valuable solution even more accessible to customers through a range of distribution channels such as Pitney Bowes Management Services, Pitney Bowes Small Business Solutions and the Internet."

iSend (available at www.pb.com/isend) seamlessly interfaces with all existing e-mail applications and it offers a convenient, around-the-clock alternative to expensive overnight package delivery and local courier services.

Some of the key enhancements incorporated into the iSend(SM) System include:

- Reliable Delivery. iSend combines the availability of e-mail with

the more robust file transfer capabilities of the web to greatly

increase the reliability of on-line file delivery.

- Universal delivery. iSend message recipients require no special

software or proprietary protocols. Anyone with e-mail and web

access can use iSend to send and receive deliveries. Everything

from word-processing documents, to graphics, to legal contracts

and even multimedia files can be delivered quickly and easily.

And, now increased performance enables businesses to transfer

large and/or confidential files four to six times faster.

- Secure delivery. Unlike regular e-mail, sensitive information is

controlled and protected through the iSend(SM) System's

point-to-point security - including robust encryption,

authentication and recipient password protection. iSend can also

defend vulnerable e-mail programs from document damage and theft.

Users can even pre-set corporate policies for secure messaging at

the enterprise level.

- Controlled delivery. iSend has sophisticated tracking features,

giving senders end-to-end visibility as to the progress of their

file delivery including return receipts and the ability to stop

transmissions. Enhanced mail list management features and

simplified set-up process making it easier to use the iSend(SM)

System

"Pitney Bowes recognizes the value of blending its core competency -- managing traditional mail processes -- with their strategic vision of delivering powerful Internet technologies to their customers", said Jeffrey C. Smith, CEO and President, Tumbleweed Communications. "Tumbleweed's IME ensures that the iSend(SM) System will fast become the solution for Pitney Bowes customers who want fast, secure and reliable document delivery over the Internet."

Pitney Bowes is a $4.2 billion premier provider of informed mail and messaging management. For more information on the iSend(SM) On-line Document Delivery System or other Pitney Bowes messaging solutions, please visit the company's web site at www.pitneybowes.com.

Tumbleweed Communications Corp. (NASDAQ:TMWD) is a leading provider of secure on-line communication services. Tumbleweed "Integrated Messaging Exchange" (IME) includes all the components necessary to develop and deploy on-line business applications involving the delivery of files and documents. Working with existing e-mail systems and on-line applications, Tumbleweed IME powers universal messaging solutions ranging from confidential, trackable business exchanges to secure, automated transactions.

Founded in 1993, Tumbleweed is headquartered in Redwood City, California. Tumbleweed partners include Sun Microsystems, Oracle, VeriSign, and RSA. Additional information about Tumbleweed Communications 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. 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. The company assumes no obligation to update information contained in this press release.

Tumbleweed is a registered trademark and Integrated Messaging Exchange and IME are trademarks of Tumbleweed Communications Corp.

    --30--kam/ny*

    CONTACT: Contact for Pitney Bowes:
             Scott Tangney, 212-684-6300
             e-mail: stangney@lobsenzstevens.com
             or
             Contact for Tumbleweed
             Lisa Poulson, 650-216-2020

    KEYWORD: CONNECTICUT CALIFORNIA
    INDUSTRY KEYWORD: TELECOMMUNICATIONS COMPUTERS/ELECTRONICS
INTERACTIVE/MULTIMEDIA/INTERNET COMED AEROSPACE/DEFENSE 
PUBLISHING PRODUCT ENTERTAINMENT