New Tumbleweed MailGate 6500 Email Security Appliance Can Process Over 1 Million Messages Per Hour; High Performance Appliance Delivers the Industry's Most Complete Solution for Enterprise Email Security

Business Wire, July 11, 2006

REDWOOD CITY, Calif. -- Tumbleweed(R) Communications Corp. (NASDAQ:TMWD), a leading provider of email security, managed file transfer, and identity validation appliance and software products, today unveiled its new high-performance MailGate(R) 6500 email security appliance. This advanced appliance can process over one million messages per hour, and offers a comprehensive solution for policy-based email security. The MailGate Appliance(TM) 6500 sets new standards for performance, enterprise scalability, and ease-of-use, allowing companies to lower costs by consolidating on fewer appliances and security point-solutions.

"Organizations are increasingly moving towards consolidating on fewer products that provide more comprehensive security," said Brian Burke, Research Manager for IDC. "A challenge facing today's enterprise-class organizations is finding an appliance that provides high performance, scalability and reduces the cost of ownership. Vendors that can effectively address the changing security needs of today's enterprise organizations will be best positioned to lead the market."

Many organizations are shifting to all-in-one security appliances to address their needs for lower costs, higher performance, easier deployment, tighter security and greater scalability. The MailGate Appliance 6500 features dual multi-core 2.4 Ghz Opteron processors with internal redundancy, hot-swappable disk drives and power supplies, and over 1.5 terabytes of storage capacity. This new appliance includes Tumbleweed's unique front panel LCD and easy configuration controls, which enable rapid network setup, display status information, and allow appliance reset with no external cabling or monitors.

The Tumbleweed MailGate Appliance 6500 delivers additional integrated features that include:

--Virus Outbreak Protection providing zero-hour defense against new virus attacks

--Advanced anti-spam eliminating over 99% of unwanted mail with virtually no false positives (0% false positives according to the VeriTest Anti-Spam Benchmark Service, Fall 2005)

--Processing power of more than 1 million messages per hour

--Bi-directional content inspection with advanced and intuitive policy controls

--Enterprise-class scalability with clustering between data centers, per-domain routing and replicated policy configuration

--Advanced rules-based TLS encryption providing policy-based secure message delivery

--Multi-language support for end-user spam management controls

"Our customers include many of the largest organizations in the world. They have rigorous performance and security demands, and we've focused on delivering solutions that scale to meet their increasing needs," said James Guthrie, Executive Vice President of Products for Tumbleweed. "The MailGate Appliance 6500 is the culmination of our years of enterprise security experience blended with a state-of-the-art platform that provides the highest possible power, flexibility, and manageability."

About the Tumbleweed MailGate Product Suite

The Tumbleweed MailGate Product Suite is a family of products for protecting, filtering and monitoring corporate email. These best-in-breed products enable businesses to manage inbound and outbound traffic, block threats, encrypt messages and optimize network performance. MailGate products include MailGate Appliance, MailGate Email Firewall(TM) software and MailGate Secure Messenger software(TM), each optimized for specific environments and security challenges.

--MailGate Appliance: A powerful and easy-to-deploy hardened Linux appliance, providing integrated network edge defense, antispam, antivirus, content filtering, policy management, and outbound encryption.

--MailGate Email Firewall: A comprehensive email security software offering, with functionality ranging from inbound threat prevention to outbound content filtering, monitoring and encryption.

--MailGate Secure Messenger: A policy-based, secure message delivery solution that inspects incoming and outgoing mail and dynamically applies user-defined encryption and routing preferences.

SAFE HARBOR STATEMENT

Tumbleweed cautions that forward-looking statements contained in this press release are based on current plans and expectations as of the date of this press release, and that a number of factors could cause the actual results to differ materially from the guidance given at this time. These factors are described in the Safe Harbor statement below.

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 functionality and performance of Tumbleweed's products. 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 16, 2006 and Form 10-Q filed May 10, 2006.