UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D/A

Under the Securities Exchange Act of 1934
(Amendment No. 5)*

SONUS NETWORKS, INC.

(Name of Issuer)

(Title of Class of Securities)

(CUSIP Number)

Darrin Payne
P.O. Box 71082
Dubai, United Arab Emirates
+971-4317-5800

(Name, Address and Telephone Number of Person
Authorized to Receive Notices and Communications)

June 18, 2008

(Date of Event which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(c), 240.13d-1(f) or 240.13d-1(g), check the following box. o

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act.

 

 

CUSIP No.		835916107		Page		2		of		9 Pages

* The calculation of the foregoing percentage is based on 271,138,012 Common Shares outstanding as of May 2, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 8, 2008.

CUSIP No.		835916107		Page		3		of		9 Pages

* The calculation of the foregoing percentage is based on 271,138,012 Common Shares outstanding as of May 2, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 8, 2008.

CUSIP No.		835916107		Page		4		of		9 Pages

* The calculation of the foregoing percentage is based on 271,138,012 Common Shares outstanding as of May 2, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 8, 2008.

CUSIP No.		835916107		Page		5		of		9 Pages

* The calculation of the foregoing percentage is based on 271,138,012 Common Shares outstanding as of May 2, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 8, 2008.

CUSIP No.		835916107		Page		6		of		9 Pages

* The calculation of the foregoing percentage is based on 271,138,012 Common Shares outstanding as of May 2, 2008, as reported in the Issuer’s Quarterly Report on Form 10-Q filed with the Securities and Exchange Commission on May 8, 2008.

EXPLANATORY NOTE

     This Amendment No. 5 amends the Statement on Schedule 13D (the “Schedule 13D”) filed with the Securities and Exchange Commission (the “Commission”) on August 6, 2007, Amendment No. 1 filed with the Commission on September 10, 2007, Amendment No. 2 filed with the Commission on December 13, 2007, Amendment No. 3 filed with the Commission on December 26, 2007 and Amendment No. 4 filed with the Commission on April 21, 2008, by Galahad Securities Limited, Legatum Capital Limited, Legatum Global Holdings Limited, Legatum Global Investment Limited and Senate Limited, acting on behalf of that certain trust formed under the laws of The Cayman Islands as of July 1, 1996. Unless otherwise defined herein, all capitalized terms shall have the meanings ascribed to them in the Schedule 13D.

Item 4. Purpose of Transaction

     The disclosure in Item 4 of the Schedule 13D is hereby amended by adding the paragraphs below as new paragraphs following the last paragraph of the current disclosure, as follows:

     At meetings in May and June 2008, the Reporting Persons met with the Issuer’s management and representatives of the board of directors to discuss certain concerns they have regarding the Issuer and to discuss certain potential courses of action. At those meetings and in a subsequent telephone conversation, the Reporting Persons suggested that the Issuer implement certain corporate governance reforms, including (i) the separation of the Chairman of the Board and the Chief Executive Officer positions, (ii) the elimination of the Issuer’s classified board structure, (iii) allowing the Issuer’s directors to be removed from the board of directors for reasons other than cause, (iv) permitting the holders of a majority of the Issuer’s outstanding common stock to call a special meeting of the Issuer’s stockholders and (v) the elimination of the supermajority voting requirements with respect to the removal of the Issuer’s directors and the approval of certain amendments to the Issuer’s certificate of incorporation and bylaws. The Reporting Persons also suggested that the Issuer (i) expand the size of the board of directors to add independent directors and grant the Reporting Persons the right to appoint two members to the board of directors, (ii) pursue a potential strategic acquisition that the Reporting Persons believe would be accretive to earnings and (iii) execute a buyback of a portion of the Issuer’s common stock.

     The Reporting Persons continue to remain interested in working collaboratively with the Issuer’s management and board of directors to implement the Reporting Persons’ suggestions. In the event that an acceptable resolution cannot be achieved, the Reporting Persons may in the future consider a variety of alternatives for achieving their goal of enhancing stockholder value, including contacting the Issuer, stockholders of the Issuer and/or other persons for purposes of discussing the Issuer, submitting or supporting one or more proposals for stockholder action at a special or annual meeting of the Issuer’s stockholders or pursuing negotiated transactions, tender offers, proxy contests or other similar actions. The Reporting Persons will also continue to evaluate the business, financial condition, management, and prospects of the Issuer, as well as conditions in the economy and the Issuer’s industry in general, and may consider the following additional future courses of action: (i) continuing to hold their shares of the Issuer’s common stock for investment; (ii) disposing of all or a portion of such shares of common stock in open market sales or in privately-negotiated transactions; or (iii) acquiring additional shares of common stock in the open market or in privately-negotiated transactions. However, the Reporting Persons have not made any decision whether to take any of the foregoing actions. The Reporting Persons reserve the right to participate, alone or with others, in plans, proposals or transactions of a similar or different nature with respect to the Issuer.

     Attached hereto as Exhibits 1, 2 and 3 are copies of letters sent by the Reporting Persons to the Issuer’s senior management and members of the Board of Directors.

     The Reporting Persons have announced their intention to withhold their vote for all of the Issuer’s nominees for election to the Issuer’s Board of Directors at the Issuer’s upcoming annual meeting of shareholders. The Reporting Persons are discussing their plans to withhold their votes for the director nominees with a limited number of other shareholders of the Issuer, consistent with applicable securities laws and regulations. A copy of the press release announcing their intention to withhold their vote and the reasons therefore is attached hereto as Exhibit 4.

     On June 13, 2008, the Reporting Persons made a filing with the Antitrust Division of the U.S. Department of Justice and the U.S. Federal Trade Commission pursuant to the Hart-Scott-Rodino Antitrust Improvements Act, as amended, fulfilling an obligation to file which arose in May 2007.

     In addition, the Reporting Persons intend to make a voluntary filing to the Committee on Foreign Investment in the United States under Section 721 of the Defense Production Act of 1950, as amended, 50 App. U.S.C. § 2170, as amended, in conjunction with their ownership in and discussions with the Issuer.

Item 7. Material to be Filed as Exhibits

     The disclosure in Item 7 of the Schedule 13D is hereby supplemented by adding the following Exhibits.

Exhibit 1 –		Letter from the Reporting Persons to the Issuer, dated June 8, 2008
Exhibit 2 –		Letter from the Reporting Persons to the Issuer, dated June 11, 2008
Exhibit 3 –		Letter from the Reporting Persons to the Issuer, dated June 18, 2008
Exhibit 4 –		Press Release of the Reporting Persons, dated June 18, 2008

SIGNATURE

     After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Dated as of June 18, 2008

Exhibit 1

8^th June 2008

Mr. Paul J. Severino, Director
Sonus Networks Inc.
7 Technology Park Drive
Westford, MA 01886

Via Electronic Mail

Dear Paul,

Thank you again for meeting with Derek Sheeler and me last Tuesday and for the call yesterday. We have appreciated the opportunity to talk about Sonus Networks with you and specifically how best to unlock the company’s tremendous potential. Thank you also for agreeing to relate our conversations to the rest of the Board. To assist you as you convene with the other Board members, we thought it might be helpful to capture the key points at this stage:

	1.		Legatum, through its affiliates, has been a stockholder in Sonus for over two years, and we currently own 25% of the company.
	2.		Over the past two years, Legatum has been a quiet and supportive stockholder even through a series of operational failures, accounting debacles and shareholder lawsuits, which together have driven the stock to near 5-year lows.
	3.		During this time Legatum representatives met with management, specifically Mr. Hassan Ahmed and Ms. Jocelyn Philbrook, several times. At each meeting we politely raised concerns and made recommendations relating both to long term strategy and immediate operational issues. Unfortunately our recommendations were seemingly ignored as none were implemented and we never received any follow up or response from management.
	4.		On May 14, we again met with Mr. Ahmed and Ms. Philbrook and gave them a presentation dated the same date which we understand was subsequently given to the Board. In the presentation we raised 5 key issues which we believe are holding the company back. We also offered a 4-point plan to address these issues. We made it clear in the meeting that we expected a point-by-point response from the Board to our plan within a one week timeframe. One day late, we received a one-page letter from Mr. Ahmed which failed to address the issues we raised.
	5.		On May 16, two days after our meeting with Mr. Ahmed and Ms. Philbrook, the company hired Dr. Nottenburg as the new CEO. We welcome the separation of the Chairman and CEO roles. Like many other stockholders we have several questions about the choice for CEO and the level of executive management of the Chairman going forward. However, we intend to keep an open mind until we hear Dr. Nottenburg’s plan to turn Sonus around and see the results of his leadership over the critical next few months.

LEGATUM LIMITED LEVEL 9, CONVENTION TOWER 71082 DUBAI, UAE		TELEPHONE +971 4 317 5800 FACSIMILE +971 4 317 5811 WWW.LEGATUM.COM

	6.		While there has been a change in the CEO, the other issues we raised remain unaddressed by the Board. Mr. Ahmed’s letter and cover note implied that we would have to wait for an indeterminate amount of time for a response, until Dr. Nottenburg “is on board”. This is unacceptable as the decision regarding whether to welcome two Legatum nominees on the Board has nothing to do with the CEO, rather it is entirely the purview of the Board. This is also the case with regard to whether or not to improve the corporate governance profile of the company. The Board does not need to ask Dr. Nottenburg whether we should improve corporate governance, this is something that can and should be done now.
	7.		The issues raised in our May 14 presentation are of immediate commercial importance to the company, and as such deserve to be addressed promptly. Our preference is to work with the Board to make this happen in a cooperative and constructive manner.
	8.		To move forward, Legatum now calls on the Board to accept a number of Legatum nominees to the Board that reflects our proportional ownership of the company before the Annual Meeting on June 20. As of today, this would be two members. We would expect our representation to remain proportional going forward. We will then work with the Board to address the issues we have raised along with the other strategic and operational issues facing the company.
	9.		We understand that the Board has a process for reviewing candidates. However, this is a process established by the Board and not law and is therefore within the Board’s discretion to modify. Nevertheless, we respect your desire to act in accordance with your process and are happy to submit our nominees for review, so long as the process is both quick and fair. Yesterday you implied that our candidates would need to sign NDAs and/or other documents which other directors, even those holding stock in the company, are not required to sign. Such discrimination could not be considered fair or in line with the existing process. We would understand, however, an approach whereby our nominees would enjoy the same rights and be bound by the same restrictions that currently apply to other directors.
	10.		We would request that the Board reconsider its decision to only consider one nominee from Legatum. Once we have this confirmation, we can move rapidly to advance discussions with our potential nominees. Simultaneously we would discuss our nominees with the Board and start the nomination and approval process.
	11.		Given the impending Annual Meeting, we would request the Board’s confirmation prior to June 11 that it will give due consideration to our two nominees so that we can plan accordingly. Any delay will make it increasingly difficult to solidify commitments from our potential nominees and complete the process prior to the Annual Meeting.
	12.		Finally, as we have stated previously, Legatum has a sincere desire to work alongside the Board and will continue to do so as long as we are confident that we are all working for the best interests of the company and its stockholders. If the issues we have raised are not able to be resolved in a satisfactory manner we will have no choice but to bring them directly to the other stockholders and are prepared to do so.

I hope this is helpful as a framework for your discussions with the other Board members. As we discussed, we do hope that we will have the opportunity to work closely together to turn Sonus around, restore credibility and re-position the company amongst employees, customers, stockholders and the investment community as the great company it can be.

We are available and more than happy to discuss these issues with you and the other directors at a mutually convenient time.

Yours sincerely,
LEGATUM LIMITED

/s/ Mark Stoleson

Mark Stoleson
President

Cc:		The Board of Directors of Sonus Networks Inc.
		Mr. Hassan J. Ahmed, Chairman and CEO
		Mr. Charles Gray, Esq.

Exhibit 2

11^th June 2008

Mr. Hassan J. Ahmed, Chairman and CEO
Mr. Paul J. Severino, Director
Sonus Networks Inc.
7 Technology Park Drive
Westford, MA 01886

Via Electronic Mail

Dear Hassan and Paul,

This letter is to further the discussion between Legatum Capital and Sonus’ board of directors on the issue of Legatum’s proportional representation on the board.  We have given significant consideration to your request to know the identities of Legatum’s nominees to the board of directors, and accordingly have decided to propose the two individuals named below, who we consider to be well-positioned to both assist in addressing many of the issues currently confronting the company, as well as to represent the interests of Sonus’ shareholders.

At this time the company suffers from a significant loss of credibility, not only in the eyes of market participants, but also with regulators and many industry professionals.  This should not be too surprising following years of missed SEC filings, multiple accounting missteps, the relatively shallow depth on the senior management bench and with corporate governance standards out of line with those of other major listed companies.  Many of these issues are not industry-specific and Legatum believes that having board members with a fresh, market-friendly perspective may be the best way to make a meaningful contribution to the company’s leadership.

Accordingly, Legatum intends to nominate Mark Stoleson, President of Legatum Capital, and Derek Sheeler, Chief Investment Officer of Legatum Capital.  In their capacity as Legatum’s two most senior executives they oversee an investment in Sonus of 67,295,079 shares of common stock of the company.  Derek Sheeler additionally owns 350,000 shares of common stock personally.  Both Mr. Stoleson and Mr. Sheeler are accomplished professionals whose sole motivation is to ensure that Sonus fulfils its tremendous business potential and maximizes shareholder value.

This is a critical time for Sonus.  The next 12-24 months are crucial in determining whether or not Sonus will be a dominant player in next generation communications, or simply another transient participant in the shifting landscape of the telecom equipment industry.  As an extraordinarily successful global investor for over two decades, Legatum is able to contribute useful insights at such a transitional moment and hopes that management and the board will welcome our involvement.

Over the last couple of years we have received numerous unsolicited approaches from other shareholders asking us to take a more active role in providing a shareholder perspective at the company.  We believe that the presence of these two candidates on the board will go some way toward reassuring investors that they have a voice where it counts.

LEGATUM LIMITED		TELEPHONE +971 4 317 5800
LEVEL 9, CONVENTION TOWER		FACSIMILE +971 4 317 5811
71082 DUBAI, UAE		WWW.LEGATUM.COM

It is Legatum’s hope that by sharing our current intentions with the board of Sonus that we can begin to work together to shape the bright future befitting the company.  By communicating our perspective we hope that this will alleviate any concerns that appear to have arisen.  This should also allow the board to expeditiously approve Legatum’s two seats and for all involved to redirect their efforts back to working together to build the most successful company possible.

Yours sincerely,
LEGATUM LIMITED

/s/ Mark Stoleson

Mark Stoleson
President

Cc:		The Board of Directors of Sonus Networks Inc. Mr. Charles Gray, Esq.

Exhibit 3

18^th June 2008

Hassan Ahmed, Chairman
Sonus Networks Inc.
7 Technology Park Drive
Westford, MA 01886

Via Electronic Mail

Dear Hassan,

Thank you for your letter dated 12^th June. We appreciate the Company’s willingness to consider a Legatum nominee to the Board of Directors. We note, however, that any shareholder is permitted to propose a candidate to the Board at any time. You are therefore offering something to which we are entitled to in any case. Moreover, your letter implies that Legatum’s nominees and Legatum itself would be subject to shareholder agreements, standstill agreements, an investigation into our source of funds and other matters. This appears to be “special” treatment outside the normal nomination process and a highly unconstructive approach to resolving the issues we have raised.

In all of our communications to date we have stated repeatedly that Legatum wishes to work with the Board to restore the Company’s credibility in the market and help position the Company to fulfil its potential. Given the fact that Legatum’s proposals have been effectively ignored, delayed or rebuffed, and compounded by the discriminatory requirements you are seeking to impose upon any Legatum nominee, we are left with no choice but to conclude that the Board is entrenched in its position and prefers to maintain the status quo rather than engage in a meaningful dialogue with its largest shareholder.

With the Company’s best interests in mind therefore, we are writing to advise you of Legatum’s intention to withhold its vote from all nominees standing for election at the Annual Meeting on 20^th June. As the company’s major shareholder it would also be appropriate to make public our intentions. And in any such public communication we would of course need to explain our rationale and the background of our dialogue with the Board and management. We also intend to speak with a limited number of other shareholders regarding our intentions.

An additional matter of serious concern to all shareholders relates to the failure by the company to supplement its proxy materials to reflect the recent material management and Board changes and send out new proxy cards in advance of the Annual Meeting.

We urge the Board to engage with Legatum immediately if there is any chance that it is willing to engage in a more serious dialogue regarding Legatum’s proposals, including fair, equal and proportional representation on the Board.

It would be in everyone’s best interests if we can find a way to avoid taking this discussion public, which would necessitate a detailed review of the company’s and the Board’s performance over the last several years. It remains our hope and preference that the Board will choose to engage constructively with Legatum to address serious shareholder concerns. Failing which, the Board’s current position gives us very few options.

LEGATUM LIMITED		TELEPHONE +971 4 317 5800
LEVEL 9, CONVENTION TOWER		FACSIMILE +971 4 317 5811
71082 DUBAI, UAE		WWW.LEGATUM.COM

Please contact me urgently if you wish to discuss this letter as we intend to proceed with our next steps imminently. Please feel free to use my mobile number and note that I am currently on East Coast time.

Yours sincerely,
LEGATUM LIMITED

/s/ Mark Stoleson

Mark Stoleson
President

Cc:		The Board of Directors of Sonus Networks Inc. Charles Gray, Esq. Akin Gump Strauss Hauer & Feld Skadden, Arps, Slate, Meagher & Flom LLP

Exhibit 4

FOR IMMEDIATE RELEASE

LEGATUM TO WITHHOLD VOTE FOR SONUS NETWORKS DIRECTORS
AT 2008 ANNUAL MEETING

18^th June 2008, NEW YORK & DUBAI - Legatum Capital, which beneficially owns approximately 25% of the shares of Sonus Networks, Inc. (NASDAQ: SONS), announced today that it intends to withhold its vote for all nominees to the board of directors of Sonus that are standing for election at Sonus’ Annual Meeting of Stockholders scheduled to be held on June 20, 2008. Legatum, which is a private, value-conscious, multi-billion dollar investment organization is Sonus’ largest shareholder.

The specific reasons that Legatum is withholding its vote include:

	•		Under the current board of directors’ leadership, Sonus’ stock price has declined to near five-year lows, which Legatum believes has led to a significant loss of investor confidence in the Company’s ability to fulfil its potential under current leadership.
	•		The three directors up for election have presided over years of poor operational performance, shareholder lawsuits, high senior management turnover, and a failure to articulate or execute an effective strategic vision.
	•		Legatum’s belief that the Company lacks transparency and its board of directors is unresponsive to shareholder concerns.

Mark Stoleson, President of Legatum Capital, said, “Legatum is withholding its vote because it believes that Sonus’ board of directors has not taken necessary action to change the way the Company is managed or to deliver value to shareholders.”

Legatum’s decision to withhold its vote also reflects its concerns about the Company’s recent announcement that Richard N. Nottenburg will replace Hassan Ahmed as CEO and be appointed to the board of directors without a shareholder vote, with Mr. Ahmed continuing on as a director and Chairman of the Board. Legatum believes that these actions demonstrate Sonus’ poor corporate governance practices, lack of transparency, and disregard for the views and interests of shareholders.

Legatum’s voting decision reflects its deep concern that to date the Company has not provided shareholders with supplemental proxy material for the upcoming Annual Meeting describing the selection of Mr. Nottenburg as the new CEO and as a director. As a result, shareholders were denied the opportunity to decide whether to elect Mr. Nottenburg to the board of directors and whether Mr. Ahmed, the Company’s former CEO, should continue on the board as Chairman.

— ENDS —

About Legatum Capital

Legatum Capital (www.legatum.com) is a private, value-conscious portfolio investor that manages a multi-billion dollar fund investing only proprietary capital in outstanding businesses with durable competitive advantages. Legatum management has invested across four continents and multiple industries with over our 20 years experience, generating exceptional returns by effectively allocating financial capital to companies and countries in transition.

Media Contacts
New York
Fred Spar
Kekst & Co. Inc.
Telephone:		+1 212 521 4813
Facsimile:		+1 212-521-4900
Email:		fred-spar@kekst.com
Dubai
Hamish Banks
Legatum
Telephone:		+971 4317 5800
Facsimile:		+971 4317 5811
Email:		hamish.banks@legatum.com