Contacts: Paul Goyette, (613) 592-2122 x.2188, paul_goyette@mitel.com …

Contacts:
Paul Goyette, (613) 592-2122 x.2188, paul_goyette@mitel.com (media)
Alex Anderson, (613) 592-2122 x.2107, alex_anderson@mitel.com (industry analysts)

            Mitel and Sun Deliver on Global OEM Agreement
 Unveil industry's first truly unified communications thin desktop, generating significant customer
                                               interest

VOICECON, Orlando, Florida ­ March 17, 2008 ­ Mitel®, a leader in IP-based voice solutions,
and Sun Microsystems, the leader in IT infrastructure, are continuing to deliver on their global
OEM agreement which offers enterprises and SMBs a complete unified communications solution
with new levels of flexibility and business process improvement for existing and future Mitel and
Sun customers worldwide. Today, Mitel and Sun are announcing the availability of the Sun Ray
Unified IP Client from Mitel in Q208 and several customers that are using or planning to use the
unified communications solution that is well-suited for both cost and security-sensitive
environments as well as for people that work remotely or are very mobile.

Mitel and Sun have committed teams of resources to further develop the joint unified
communications solutions and take them to market. Earlier this month Mitel announced the Q208
availability of the Mitel Communications Suite on the Sun Fire X4150, which introduces the ability
to consolidate mission critical voice applications such as messaging, mobility, conferencing and
Microsoft® Office Communications Server 2007 in the data room environment.

With the Sun Ray Unified IP Client, Mitel has taken the ultra thin client Sun Ray technology and
created a slim module that snaps securely onto Mitel IP phones to create the industry's first truly
unified communications desktop. This allows users to securely "hot desk" into both the Mitel IP
phones and the Sun RayTM thin client terminals using a personal, authenticated Java Card.

The Sun Ray Unified IP Client provides voice and data services at any workstation on the
network, dramatically reducing desktop cost and complexity while preserving the familiar, proven,
telephone device. The simultaneous hot desking takes place within five seconds of the Java Card
being inserted into the Sun thin client on any terminal within the network, providing the user with
access to their desktop profile as well as advanced unified communications capabilities, such as
mobility, unified messaging, video streaming, and presence information.

"The Sun Ray Unified IP Client delivers a secure unified computing and communications
environment fully integrated into our world renowned Sun Ray solution, " said Peter Ewens, Sun's
vice president of global OEM. "This combined solution is also among the industry's most energy
efficient, providing ongoing capex and opex savings through the elimination of power-hungry
desktop PCs and the reduced energy consumption of low power Mitel IP phones."

The Sun solutions Powered by Mitel have been designed to significantly reduce power
consumption with a combined nine Watts required to power the Sun Ray Thin Client and Mitel IP
phone compared with 80 Watt PC/60 Watt laptop and 10 Watt IP phones. Additional power
savings are realized through the reduction of servers provided by the pre-integrated Mitel
Communications Suite that incorporates the Mitel Communications Director call control software.

"With first releases around Sun Ray Unified IP Client, NuPoint Messenger IP, and Mitel
Communications Suite, Sun and Mitel are introducing a whole new era in voice and data
communications," said Stephen Beamish, Mitel's vice president of Business Development and
Strategic Alliances. "These Sun, `Powered by Mitel' solutions make it even easier for businesses
to enjoy the many advantages of unified communications to address the emerging needs of
distributed, flexible, mobile work environments. These solutions are the first deliverables in a
relationship with Sun where the industry can expect more to come in the next several months."

Food services giant Deli XL (www.delixl.nl) with approximately 2,000 employees in 30 locations
throughout The Netherlands and Belgium, has migrated away from an Ericsson voice
communications platform to the Sun Ray Thin Client and Mitel Communications Suite IP
applications architecture.

"We selected the joint Mitel-Sun solution based on the flexibility it provides to optimize our
customer contact center operations, increased customer data security delivered by the Sun
platform, and the reduced power consumption of the combined computing and telephony
platforms," said Martin Pluijgers, manager IT Support, Deli XL. "With this solution we have a
future proof customer contact solution that will ensure our continued market leadership in the
highly competitive foodservice market."

Foundation for Enhanced Unified Communications

!"   Mitel Communications Suite ­ A pre-integrated unified communications solution that allows
     Mitel's flagship Communications Director call control software to reside on Sun servers and
     consolidate applications such as Mitel NuPoint MessengerTM IP, Mitel Live Business
     Gateway, Mitel Teleworker Solution, Mitel Mobile Extension, and Mitel Audio and Web
     Conferencing all on a single server for simplified, cost effective deployment of unified
     communications solutions.

!"   Mitel Customer Interaction Solutions ­ Mitel has configured its award winning Contact
     Center Solution integration into the Sun Ray Unified IP Client. Users in a contact center
     environment can log on as an ACD agent and retain all the same features and functionalities
     associated with a Mitel Contact Center ACD Agent. Mitel's Customer Interaction Solutions
     are a Windows-based application that also allows for full Office Communications Server 2007
     integration.

!"   Mitel Mobile Extension ­ Mitel's Mobile Extension software allows for multiple devices to
     simultaneously ring thus ensuring that the user receives the majority of phone calls. The user
     has the ability to provide customers, colleagues, suppliers, and partners, one contact number
     which ensures that both the contact number provided and the user's associated mobile
     phone ring simultaneously. Additionally the user has the ability to transfer the call seamlessly
     to any hot desk Sun Ray Unified IP Client thus eliminating any additional mobile phone
     charge and also allowing the user to access the rich features associated with the Mitel 3300
     IP Communications Platform (ICP).

!"   Mitel Teleworker Solution ­ Mitel Teleworker Solution integrates the Sun Ray Unified IP
     Client with a Mitel IP phone as a teleworker for secure access to corporate information. Both
     the Teleworker Solution and Sun Ray devices are in effect thin clients allowing zero security
     threat from intruders.

!"   Mitel NuPoint MessengerTM IP Release 12 ­ Part of Mitel Communications Suite of
     applications that integrates with the Sun Ray IP thin client, NuPoint Messenger IP Release 12
     provides Speech Auto Attendant with Text-to-Speech playback of called party names and
     provides the presence infrastructure for open standards interface to commercial presence
     servers. The Speech Auto Attendant is the first application within the NuPoint Messenger IP
     product family to be presence-enabled with portions of NuPoint such as Call Director to follow
     in future releases.
Founded in 1988, The Telephone Connection of Los Angeles, Inc. (TTC) provides enhanced
services such as follow-me, conference calling, and virtual automated attendant and voice mail
service catering primarily to the medical community in Southern California.

"There are some very compelling benefits to the solution Sun and Mitel are bringing to market
given the nature of the services we provide to the medical community," said Marc O'Krent,
president, The Telephone Connection of Los Angeles, Inc. "As thin clients allowing zero security
threat from intruders, the Sun Ray Unified IP thin client married with a Mitel Teleworker Solution
using Secure Real Time Protocol rather than VPN connectivity provides much stronger security
for each individual user accessing private medical information. We think this partnership between
Mitel and Sun Microsystems will continue to deliver innovative solutions like the Unified IP client
that will benefit companies such as ours for a long time."

Mitel Exclusive Business Partner Firstline Communications (www.firstline.net) is deploying the
solution in-house to all of its employees. They will be running call control on Mitel
Communications Suite and using the Sun Ray Unified IP Client with hot desking and Mobile
Extension. They are running Windows OS and will continue to benefit from Office
Communications Server 2007 integration with Mitel.

"Our focus continues to be to help enterprises with fewer than 2,500 users to migrate into a IP
environment," said Tim Maio, president, Firstline Communications Inc. "Mitel and Sun are making
it even easier for businesses to enjoy the many advantages of IP communications by reducing
the complexity, cost, and management of their voice environment by running Mitel call control and
applications on a single Sun server and managing computing and telephony as one unified
communications solution."

The SunRay Unified IP Client from Mitel as well as the Mitel Communications Suite on Sun
servers will be sold directly to enterprise accounts by Sun and Mitel and will be taken to the
general business market through select Sun and Mitel channel partners supported by Sun and
select Sun channel partners.

About Mitel
Mitel delivers flexibility and simplicity in smart unified communications solutions and applications
for organizations of all sizes. Mitel is reinventing how successful organizations gain competitive
advantage by easily collaborating and communicating over distance and time with customers,
colleagues and partners. Mitel's (www.mitel.com) US headquarters are in Phoenix, AZ. Global
headquarters are in Ottawa, Canada, with offices, partners, and resellers worldwide.

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