Messages On the Nation's Largest Wireless Data Network Protected with Certicom's Advanced Security Technology 

RESTON, VA - December 5, 2001 - Motient Corporation (NASDAQ: MTNT), owner and operator of the nation's largest wireless data network, announced today that it would enhance the security level of transmissions over its two-way network through the use of security software from Certicom Corporation (NASDAQ: CERT; TSE: CIC), a leading provider of mobile e-business security. The agreement extends for three years and allows Motient to incorporate Certicom's SSL Plus™, WTLS Plus™ and WTLS Plus - Java Platforms software applications into Motient's wireless email solutions, thus ensuring the integrity and privacy of the information that is exchanged. 

Certicom's technology will be used initially in Motient's eLink^SM wireless email service that is to be offered with Motient's new wireless modem for the Palm VTM series handhelds - the MobileModem. Certicom's WTLS Plus software application will be used to encrypt wireless email transmitted from the Palm handheld via the MobileModem. Palm users will now enjoy access to real-time, always-on, encrypted wireless email virtually anywhere in the country. 

"Messages sent over Motient's wireless data network are important and we are committed to maintaining their total privacy and complete security," said Peter B. Belman, vice president of Marketing and Brand Management for Motient. "Motient's customers are predominantly large enterprises who demand high-levels of network security when they integrate wireless data solutions. Motient is taking a leadership role in furthering the security of our network by partnering with the leader in the mobile Internet security industry, Certicom. Certicom's technology will be employed in a number of our wireless email services, providing our subscribers with the security they need and demand." 

"Motient is a leader in providing wireless solutions to the Fortune 1000 and their mobile workforce. Field service organizations and mobile professionals alike utilize Motient's solutions on a daily basis to relay critical information in real time," said Prakash Panjwani, senior vice president of Business Development for Certicom. "Subscribers are demanding the highest levels of security when it comes to their wireless messaging solutions. Our relationship provides Motient subscribers with the most trusted wireless security technology available today." 

About Certicom
Certicom is a leading provider of information security software and services, specializing in solutions for mobile e-business. The company's products and services are specifically designed to address the challenges imposed by a wireless data environment. Certicom's solutions incorporate its efficient encryption technology and are based on industry standards for information security that utilize public key cryptography. Certicom's products are currently licensed to more than 200 customers including Cisco Systems, Inc., Handspring Inc., Motorola, Inc., Nortel Networks, Openwave Systems, Inc., Palm, Inc., QUALCOMM, Inc., Research In Motion Ltd., Sony International (Europe) GmbH and Verizon Communications Inc. Certicom's headquarters and worldwide sales and marketing operations are based in the Silicon Valley in Hayward. For more information, visit Certicom's Web site at http://www.certicom.com. 

Certicom, SSL Plus and WTLS Plus are trademarks of Certicom Corp. All other companies and products listed herein are trademarks or registered trademarks of their respective holders. 

Except for historical information contained herein, this press release contains forward-looking statements that involve risks and uncertainties. Actual results may differ materially. Factors that might cause a difference include, but are not limited to, those relating to the acceptance of mobile and wireless devices and the continued growth of e-commerce and m-commerce, the increase of the demand for mutual authentication in m-commerce transactions, the acceptance of Elliptic Curve Cryptography (ECC) technology as an industry standard, the market acceptance of our principal products and sales of our customer's products, the impact of competitive products and technologies, the possibility of our products infringing patents and other intellectual property of fourth parties, and costs of product development. Certicom will not update these forward-looking statements to reflect events or circumstances after the date hereof. More detailed information about potential factors that could affect Certicom's financial results is included in the documents Certicom files from time to time with the Securities and Exchange Commission and Canadian securities regulatory authorities. 

About Motient
Motient (www.motient.com) owns and operates the nation's largest two-way wireless packet data network - the MotientTM network - and provides a wide-range of mobile and Internet communications services principally to business customers and enterprises. The company provides eLinkSM and BlackBerryTM by Motient two-way wireless email services. Motient's wireless email services operate on the RIM 850 and RIM 857 Wireless HandheldsTM and Motient's MobileModem for the Palm VTM series handhelds. Motient serves a variety of markets including mobile professionals, telemetry, transportation and field service, offering coverage to all 50 states, Puerto Rico and the U.S. Virgin Islands. 

eLink is a service mark and Motient is a trademark of Motient Corporation. The BlackBerry and RIM families of related marks, images and symbols are the exclusive properties of, and trademarks of Research In Motion Limited and are used by permission. "BlackBerry by Motient" - used by permission. Palm V is a trademark of Palm, Inc. 

Factors that could cause actual results to differ materially from those in the forward-looking statements in this news release are described in Motient Corporation's registration statement on Form S-4 (File no. 333-63826) and in Motient's annual report on Form 10-K for the year ended December 31, 2000 and its other periodic filings and reports with the Securities and Exchange Commission. Copies of such reports and filings are available upon request from Motient's Investor Relations Department. 

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