MSV Selects Nortel for An Industry First Hybrid Satellite-Terrestrial Network Trial

Nortel 4G and IMS Innovations to Support Advanced Voice and Multimedia Services for Ubiquitous and Hyperconnected Mobile Broadband Communications

Mobile Satellite Ventures, L.P. (MSV), one of North America’s leading providers of mobile satellite communications services, will deploy what is believe to be the first integrated 4G and satellite broadband trial powered by Nortel* [NYSE/TSX: NT] mobile WiMAX and IMS technologies. The hybrid satellite-terrestrial trial was announced today at CTIA Wireless 2007, the industry’s premier wireless event.

MSV is designing a next-generation integrated network, incorporating the benefits of both terrestrial and satellite wireless communications systems, for customers across the United States and Canada. “This trial is a significant step toward next-generation mobility,” said Drew Caplan, MSV chief network officer. “Nortel’s 4G and IMS expertise will help us demonstrate our transparency network architecture to support hybrid satellite-terrestrial communications on the basis of a 4G broadband platform, enabling new dimensions of service for our customers.”

The trial with Nortel, which will be conducted in the Reston, Virginia area, will initially feature high-speed wireless voice, data and Web access, file sharing, and VoIP connectivity using residential gateway devices and PC Cards for users in fixed and portable modes of use. Subsequently, MSV expects to incorporate push-to-talk, video calling, picture-caller ID, and presence capabilities, full MSS/ATC integration, and support for a range of mobile devices. Nortel will integrate its WiMAX and IMS connectivity as well as devices and ASIC technology from Kyocera, WiNetworks, and Runcom Technologies.

“Combining the FCC’s and Industry Canada’s ATC rulings with the broadband capabilities of WiMAX and the service delivery capabilities of IMS could support new telecom models, giving players like MSV the tools to deliver the services that consumers and enterprises want, at a palatable pricepoint,” said Peter Jarich, prinicipal analyst with Current Analysis. “Nortel has been talking about WiMAX services in the 1.5 GHz spectrum for some time. A trial with MSV proves out the opportunity while giving MSV the tools to complement its existing satellite system with a new terrestrial component, expanding wireless services with prospectively new business models and into new areas…potentially even those not covered by traditional carriers.”

“The rapid blurring of boundaries between telecom, broadcast, and broadband is challenging the limits of traditional communications networks and giving bold new players like MSV a chance to get in on the game,” said Peter MacKinnon, general manager, WiMAX, Nortel. “The enablers are technologies like WiMAX and IMS through which broadband, video and voice services can be seamlessly delivered — from the desktop, to the living room, and out into the community. Now, the sky’s the limit with MSV adding satellite to the mix.”

Nortel equipment used in the trial will include WiMAX base stations and terminals, ancillary cell site gear, an IP core network, signaling equipment, authentication servers, media gateways, optical transport and IMS core elements. In addition, Nortel will provide design, network management and maintenance services from the Nortel Global Services portfolio for the entire trial infrastructure. MSV plans to build a next-generation integrated network, which incorporates the benefits of both terrestrial, and satellite wireless communications systems. MSV currently offers a range of mobile satellite services (MSS) using two geostationary satellites that support the delivery of two-way radio (PTT), mobile data, voice and fax services to business and government subscribers across the United States and Canada.

Nortel’s 4G WiMAX and IMS innovations improve the subscriber’s communication experience and deliver the one of the highest network performances with one of the most competitive costs per megabit in the industry. Nortel’s WiMAX technology is built on a foundation of OFDM-MIMO, a combination of innovative transmission and antenna technologies that maximizes spectrum to deliver the lightning-fast speeds and high bandwidth essential to high-quality mobile video and TV.

About MSV

MSV is developing a state-of-the-art hybrid satellite-terrestrial communications network, which it expects will provide seamless, transparent and ubiquitous wireless coverage of the United States and Canada to conventional handsets. MSV holds the first FCC license to provide hybrid satellite-terrestrial services. MSV plans to launch two satellites for coverage of the United States and Canada, which are expected to be among the largest and most powerful commercial satellites ever built. When completed, the network is expected to support communications in a variety of areas including public safety, homeland security, aviation, transportation and entertainment, by providing a platform for interoperable, user-friendly and feature-rich voice and high-speed data services. MSV is majority owned and controlled by SkyTerra Communications, Inc. (OTCBB:SKYT).

About Nortel

Nortel is a recognized leader in delivering communications capabilities that make the promise of Business Made Simple a reality for our customers. Our next-generation technologies, for both service provider and enterprise networks, support multimedia and business-critical applications. Nortel’s technologies are designed to help eliminate today’s barriers to efficiency, speed and performance by simplifying networks and connecting people to the information they need, when they need it. Nortel does business in more than 150 countries around the world. For more information, visit Nortel on the Web at www.nortel.com. For the latest Nortel news, visit www.nortel.com/news.

Certain statements in this press release may contain words such as “could”, “expects”, “may”, “anticipates”, “believes”, “intends”, “estimates”, “targets”, “envisions”, “seeks” and other similar language and are considered forward-looking statements or information under applicable securities legislation. These statements are based on Nortel’s current expectations, estimates, forecasts and projections about the operating environment, economies and markets in which Nortel operates. These statements are subject to important assumptions, risks and uncertainties, which are difficult to predict and the actual outcome may be materially different. Further, actual results or events could differ materially from those contemplated in forward-looking statements as a result of the following (i) risks and uncertainties relating to Nortel’s restatements and related matters including: Nortel’s most recent restatement and two previous restatements of its financial statements and related events; the negative impact on Nortel and NNL of their most recent restatement and delay in filing their financial statements and related periodic reports; legal judgments, fines, penalties or settlements, or any substantial regulatory fines or other penalties or sanctions, related to the ongoing regulatory and criminal investigations of Nortel in the U.S. and Canada; any significant pending civil litigation actions not encompassed by Nortel’s proposed class action settlement; any substantial cash payment and/or significant dilution of Nortel’s existing equity positions resulting from the approval of its proposed class action settlement; any unsuccessful remediation of Nortel’s material weaknesses in internal control over financial reporting resulting in an inability to report Nortel’s results of operations and financial condition accurately and in a timely manner; the time required to implement Nortel’s remedial measures; Nortel’s inability to access, in its current form, its shelf registration filed with the United States Securities and Exchange Commission (SEC), and Nortel’s below investment grade credit rating and any further adverse effect on its credit rating due to Nortel’s restatements of its financial statements; any adverse affect on Nortel’s business and market price of its publicly traded securities arising from continuing negative publicity related to Nortel’s restatements; Nortel’s potential inability to attract or retain the personnel necessary to achieve its business objectives; any breach by Nortel of the continued listing requirements of the NYSE or TSX causing the NYSE and/or the TSX to commence suspension or delisting procedures; (ii) risks and uncertainties relating to Nortel’s business including: yearly and quarterly fluctuations of Nortel’s operating results; reduced demand and pricing pressures for its products due to global economic conditions, significant competition, competitive pricing practice, cautious capital spending by customers, increased industry consolidation, rapidly changing technologies, evolving industry standards, frequent new product introductions and short product life cycles, and other trends and industry characteristics affecting the telecommunications industry; the sufficiency of recently announced restructuring actions, including the potential for higher actual costs to be incurred in connection with these restructuring actions compared to the estimated costs of such actions and the ability to achieve the targeted cost savings and reductions of Nortel’s unfunded pension liability deficit; any material and adverse affects on Nortel’s performance if its expectations regarding market demand for particular products prove to be wrong or because of certain barriers in its efforts to expand internationally; any reduction in Nortel’s operating results and any related volatility in the market price of its publicly traded securities arising from any decline in its gross margin, or fluctuations in foreign currency exchange rates; any negative developments associated with Nortel’s supply contract and contract manufacturing agreements including as a result of using a sole supplier for key optical networking solutions components, and any defects or errors in Nortel’s current or planned products; any negative impact to Nortel of its failure to achieve its business transformation objective; additional valuation allowances for all or a portion of its deferred tax assets; Nortel’s failure to protect its intellectual property rights, or any adverse judgments or settlements arising out of disputes regarding intellectual property; changes in regulation of the Internet and/or other aspects of the industry; Nortel’s failure to successfully operate or integrate its strategic acquisitions, or failure to consummate or succeed with its strategic alliances; any negative effect of Nortel’s failure to evolve adequately its financial and managerial control and reporting systems and processes, manage and grow its business, or create an effective risk management strategy; and (iii) risks and uncertainties relating to Nortel’s liquidity, financing arrangements and capital including: the impact of Nortel’s most recent restatement and two previous restatements of its financial statements; any inability of Nortel to manage cash flow fluctuations to fund working capital requirements or achieve its business objectives in a timely manner or obtain additional sources of funding; high levels of debt, limitations on Nortel capitalizing on business opportunities because of support facility covenants, or on obtaining additional secured debt pursuant to the provisions of indentures governing certain of Nortel’s public debt issues and the provisions of its support facility; any increase of restricted cash requirements for Nortel if it is unable to secure alternative support for obligations arising from certain normal course business activities, or any inability of Nortel’s subsidiaries to provide it with sufficient funding; any negative effect to Nortel of the need to make larger defined benefit plans contributions in the future or exposure to customer credit risks or inability of customers to fulfill payment obligations under customer financing arrangements; any negative impact on Nortel’s ability to make future acquisitions, raise capital, issue debt and retain employees arising from stock price volatility and further declines in the market price of Nortel’s publicly traded securities, or the share consolidation resulting in a lower total market capitalization or adverse effect on the liquidity of Nortel’s common shares. For additional information with respect to certain of these and other factors, see Nortel’s Annual Report on Form10-K/A, Quarterly Reports on Form 10-Q and other securities filings with the SEC. Unless otherwise required by applicable securities laws, Nortel disclaims any intention or obligation to update or revise any forward-looking statements, whether as a result of new information, future events or otherwise.