Mitel's Credit Rating Raised by Standard & Poor's

OTTAWA, May 3, 2010 (GlobeNewswire via COMTEX News Network)

Mitel Networks Corporation (Nasdaq:MITL), a leading provider of IP-based communications solutions, today announced that on April 29, 2010, Standard & Poor's (S&P) Rating Services raised Mitel's long-term corporate credit rating to a 'B' from 'B-' and attached an outlook of "stable" to Mitel's credit rating.

In its research update S&P states, "The upgrade follows the completion of Mitel's initial public offering (IPO) of its shares on April 27, 2010, for gross proceeds of about US$150 million. Proceeds from the IPO will reduce adjusted debt by about 31% and meaningfully improve the company's financial flexibility." S&P also concludes, "The stable outlook reflects our view that Mitel should be able to sustain its improved adjusted debt leverage and corresponding credit metrics in the near term."

"I am pleased that S&P has recognized the improvement in Mitel's financial strength and the reduction in our leverage resulting from the successful completion of our initial public offering," commented Steve Spooner, CFO, Mitel Networks.

Forward-Looking Statements

Some of the statements in this press release are forward-looking statements within the meaning of applicable U.S. and Canadian securities laws that reflect Mitel's current views with respect to future events and its financial results, performance, financial position or achievements. Statements that include the words "may," "will," "should," "could," "estimate," "continue," "expect," "intend," "plan," "predict," "potential," "believe," "project," "anticipate" and similar statements of a forward-looking nature, or the negatives of those statements, identify forward-looking statements. In particular, this press release may contain forward looking statements pertaining to, among other matters: general global economic conditions; Mitel's business strategy; Mitel's plans and objectives for future operations; Mitel's industry; Mitel's future economic performance, profitability and financial condition; the costs of operating as a public company; and Mitel's research and development expenditures. These forward-looking statements reflect Mitel's current views with respect to future events and are based on assumptions and subject to risks and uncertainties. In making these statements we have made assumptions regarding, among other things: no unforeseen changes occurring in the competitive landscape that would affect our industry; a stable or recovering economic environment; no significant event occurring outside the ordinary course of our business; and stable foreign exchange and interest rates. In making these statements we have made assumptions regarding, among other things: no unforeseen changes occurring in the competitive landscape that would affect our industry; a stable or recovering economic environment; no significant event occurring outside the ordinary course of our business; and stable foreign exchange and interest rates. Actual events or Mitel's results, performance, financial position or achievements could differ materially from those contemplated, expressed or implied by such forward-looking statements as a result of various risks and uncertainties, including the risks factors described under the heading "Risk Factors" in Mitel's prospectus, dated April 21, 2010, which has been filed with the U.S. Securities and Exchange Commission and Canadian securities authorities. Except as required by law, Mitel is under no obligation to update any forward-looking statement, whether as a result of new information, future events or otherwise.

About Mitel

Mitel Networks offers a comprehensive portfolio of IP-based communications solutions, which consists of IP telephony platforms, unified communications and collaboration applications and managed and network services. By integrating voice, video and data communications with business applications, Mitel enables businesses to improve their performance. Mitel is a leader in the market evolution to unified communications and collaboration, enabling customers to move beyond basic fixed telephony and disparate communications tools toward integrated multi-media communications and collaboration between users, wherever they may be located. Mitel's U.S. headquarters are in Phoenix, Arizona. Global headquarters are in Ottawa, Canada, with offices, partners, and resellers worldwide.

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SOURCE: Mitel Networks Corporation

Contact Information

Mitel Networks Corporation Media Danielle McNeil (613) 592-2122 x4643 danielle_mcneil@mitel.com Industry Analyst Kevin Johnson (613) 592-2122 x6690 kevin_johnson@mitel.com Investor Relations Cynthia Hiponia (613) 592-2122 x1992 investorrelations@mitel.com

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