Exhibit 4.20**AMENDMENT TO NOTES**Relating to the Company’s Senior Secured Increasing Rate Notes Due 2007, issued July 1, 2005,Tranche A Senior Secured Increasing Rate Notes Due 2007, issued March 14, 2006, Tranche B SeniorSecured Increasing Rate Notes Due 2007, issued December 21, 2006, and Tranche C Senior SecuredIncreasing Rate Notes Due 2007, issued April 3, 2007     This AMENDMENT (this “Amendment”), dated as of June 27, 2007, among VIATEL HOLDING(BERMUDA) LIMITED (the “Company”) and the holders (the “Noteholders”) of theCompany’s Senior Secured Increasing Rate Notes Due 2007, issued July 1, 2005, as amended (the“2005 Notes”), Tranche A Senior Secured Increasing Rate Notes Due 2007, issued March 14,2006, as amended (the “March 2006 Notes”), Tranche B Senior Secured Increasing Rate NotesDue 2007, issued December 21, 2006, as amended (the “December 2006 Notes”), and Tranche CSenior Secured Increasing Rate Notes Due 2007, issued April 3, 2007 (the “April 2007Notes”, and together with the 2005 Notes, the March 2006 Notes, the December 2006 Notes, andall Additional Notes (as defined in the 2005 Notes, March 2006 Notes, December 2006 Notes and April2007 Notes) issued pursuant thereto, the “Notes”), issued pursuant to that certainInvestment and Note Purchase Agreement dated as of June 23, 2005, by and among the Company and thepurchasers named therein, as amended (the “Note Purchase Agreement”) is made with referenceto the Note Purchase Agreement and the Notes.WITNESSETH :     WHEREAS, the Company issued and sold US$16,000,000 in aggregate principal amount of Notes onJuly 1, 2005, US$8,802,600 in aggregate principal amount of Notes on March 14, 2006, US$13,011,120in aggregate principal amount of Notes on December 21, 2006, and US$13,011,120 in aggregateprincipal amount of Notes on April 3, 2007, which Notes are held by the Noteholders in the amountsset forth opposite their respective names on Schedule I hereto;     WHEREAS, the Notes currently provide that the Company shall on the Maturity Date (as definedin the Notes) pay the Noteholders an amount equal to the aggregate principal amount of the Notesthen outstanding, plus accrued and unpaid interest thereon;     WHEREAS, the Notes currently define the Maturity Date as July 1, 2007;     WHEREAS, the Company hereby requests that the Noteholders amend the Notes to extend theMaturity Date of the Notes from July 1, 2007 to July 1, 2008;     WHEREAS, the Noteholders have agreed to such extension provided that the interest rateapplicable to each series of Notes is increased by 1% *per annum*as of July 1, 2007;     NOW, THEREFORE, in consideration of the premises and the agreements, provisions and covenantsherein contained, the Company and the Noteholders agree as follows:A. Definitions
 

 
     Capitalized terms used herein and not otherwise defined have the meanings ascribed to them inthe Notes.B. Amendment to the Notes     1. The preamble of the Notes is hereby amended by deleting the reference to “July 1, 2007” inthe first sentence thereof and substituting therefor the following:“July 1, 2008”     2. Section 1.1(b) of the 2005 Notes is hereby amended by deleting such section andsubstituting therefor the following:“(b) Interest shall be payable semi-annually, in arrears, on each July 15 andJanuary 15 after the issuance of this Note (the “Interest Payment Dates”);provided, however, that the first Interest Payment Date shall be January 15, 2006.Interest shall accrue on the unpaid principal amount of this Note at the rate of 12%*per annum*from the Closing Date, or from the most recent Interest Payment Date forwhich the applicable interest payment has been made, until June 30, 2007; *providedfurther*, *that*interest shall accrue on the unpaid principal amount of this Note atthe rate of 14.5% *per annum*from July 1, 2007, or from the most recent InterestPayment Date for which the applicable interest payment has been made, until theprincipal amount of this Note is paid in full; *provided further*, *that*such interestrate shall increase by 0.50% *per annum*on each Interest Payment Date beginning onJanuary 15, 2006 (such interest rate as of any date of determination, the“Applicable Rate”). Notwithstanding the foregoing, interest accruing beforeJanuary 15, 2008 may, at the election of the Company, be paid on the applicableInterest Payment Date in the form of Additional Notes. Interest on this Note shallbe computed on the basis of a 360-day year composed of twelve 30-day months.”     3. Section 1.1(b) of the March 2006 Notes is hereby amended by deleting such section andsubstituting therefor the following:“(b) Interest shall be payable semi-annually, in arrears, on each July 15 andJanuary 15 after the issuance of this Note (the “Interest Payment Dates”);provided, however, that the first Interest Payment Date shall be July 15, 2006.Interest shall accrue on the unpaid principal amount of this Note at the rate of12.5% *per annum*from the Closing Date, or from the most recent Interest Payment Datefor which the applicable interest payment has been made, until June 30, 2007;*provided further*, *that*interest shall accrue on the unpaid principal amount of thisNote at the rate of 14.5% *per annum*from July 1, 2007, or from the most recentInterest Payment Date for which the applicable interest payment has been made, untilthe principal amount of this Note is paid in full; *provided further*, *that*suchinterest rate shall increase by 0.50% *per annum*on each Interest Payment Datebeginning on July 15, 2006 (such interest rate as of any date of determination, the“Applicable Rate”). Notwithstanding the foregoing, interest
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accruing before January 15, 2008 may, at the election of the Company, be paid on theapplicable Interest Payment Date in the form of Additional Notes. Interest on thisNote shall be computed on the basis of a 360-day year composed of twelve 30-daymonths.”     4. Section 1.1(b) of the December 2006 Notes and the April 2007 Notes is hereby amended bydeleting such section and substituting therefor the following:“(b) Interest shall be payable semi-annually, in arrears, on each July 15 andJanuary 15 after the issuance of this Note (the “Interest Payment Dates”);provided, however, that the first Interest Payment Date shall be July 15, 2007.Interest shall accrue on the unpaid principal amount of this Note at the rate of12.75% *per annum*from the Closing Date, or from the most recent Interest PaymentDate for which the applicable interest payment has been made, until June 30, 2007;*provided further*, *that*interest shall accrue on the unpaid principal amount of thisNote at the rate of 13.75% *per annum*from July 1, 2007, or from the most recentInterest Payment Date for which the applicable interest payment has been made, untilthe principal amount of this Note is paid in full; *provided further*, *that*suchinterest rate shall increase by 0.50% *per annum*on each Interest Payment Datebeginning on July 15, 2007 (such interest rate as of any date of determination, the“Applicable Rate”). Notwithstanding the foregoing, interest accruing beforeJanuary 15, 2008 may, at the election of the Company, be paid on the applicableInterest Payment Date in the form of Additional Notes. Interest on this Note shallbe computed on the basis of a 360-day year composed of twelve 30-day months.”     5. Article 10 of the Notes is hereby amended by inserting the following section 10.15 at theend of such article:“Section 10.15. Usury Savings. Notwithstanding anything herein to thecontrary, if at any time the applicable interest rate, together with all fees andcharges that are treated as interest under applicable law (collectively, the“Charges”), as provided for herein or in any other document executed inconnection herewith, or otherwise contracted for, charged, received, taken orreserved by any of the Noteholders, shall exceed the maximum lawful rate (the“Maximum Rate”) that may be contracted for, charged, taken, received orreserved by such Noteholder in accordance with applicable law, the rate of interestpayable hereunder, together with all Charges payable to such Noteholder, shall belimited to the Maximum Rate. In the event that the Noteholders ever receive anyamount as a result of interest and other Charges paid in excess of the Maximum Rate,such amount which would be excessive interest shall be applied to the reduction ofthe principal sum hereof, and if the principal sum is paid in full, any remainingexcess shall forthwith be paid to the Company.”     6. Section 9.1 of the Notes is hereby amended by inserting the following new definitions inalphabetical order:
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          ““Charges” has the meaning set forth in Section 10.15.”          ““Maximum Rate” has the meaning set forth in Section 10.15.”C. Action of the holder of the Special Share     Each of Morgan Stanley & Co. Incorporated, Värde Partners, Inc. and Stonehill InstitutionalPartners, L.P., each in its capacity as a holder of Existing Notes, hereby consents to MorganStanley & Co. Incorporated, as holder of the Special Share (as defined in the Note PurchaseAgreement), consenting to the Company’s execution of this Amendment and entry into the transactionsrelated thereto.D. Conditions to Effectiveness     1. This Amendment shall take effect on the date (the “Amendment Effective Date”) on orbefore July 1, 2007 when all of the following shall have occurred:          (a) Each of the Company and the Noteholders shall have signed a counterpart hereof (whetherthe same or different counterparts) and shall have delivered (including by way of e-mail ortelecopier) the same to each other;          (b) The Company shall have delivered to the Noteholders such other documents, agreements,instruments and information as the Noteholders may reasonably request;          (c) The Company shall have paid in full all outstanding statements for fees and expenses ofthe Noteholders (including, without limitation, the fees and disbursements of Wachtell, Lipton,Rosen & Katz), incurred in connection with this Amendment and all other documents delivered inconnection herewith and therewith; and          (d) The Company, the Law Debenture Trust Corporation P.L.C., the Noteholders and certainsubsidiaries of the Company shall have executed and delivered to the Noteholders an executedcounterpart of the Amendment to Security Trust and Intercreditor Deed dated                      ___, 2007 whichamendment shall be in form and substance satisfactory to the Noteholders.E. Miscellaneous Provisions     1. In order to induce the Noteholders to enter into this Amendment, the Company herebyrepresents and warrants that:          (a) Except as expressly waived hereby (i) there exists no Default or Event of Default underthe Notes as of the date hereof, and (ii) except as set forth on Schedule II hereto, allof the representations and warranties contained in the Note Purchase Agreement are true and correctin all material respects as of the Amendment Effective Date (or, if any such representation orwarranty is expressly stated to have been made as of a specific date, as of such specific date);and
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          (b) The written statements and information contained in this Amendment, the Notes, the NotePurchase Agreement, the Security Documents, and the amendments thereto, and the other documents,certificates and statements furnished to the Noteholders on or prior to the Amendment EffectiveDate by or on behalf of any of the Company or the Guarantors for use in connection with thetransactions contemplated by this Amendment, the Notes, the Note Purchase Agreement and theSecurity Documents, taken as a whole, do not, as of the Amendment Effective Date, contain anyuntrue statement of a material fact or omit to state a material fact necessary in order to make thestatements contained therein not misleading. There is no fact known to any Loan Party that couldreasonably be expected to have a Material Adverse Effect (as defined in the Note PurchaseAgreement) that has not been expressly disclosed herein (including without limitation ScheduleII hereto), in the Notes, the Note Purchase Agreement, Security Documents or in any otherdocuments, certificates and statements furnished to the Noteholders for use in connection with thetransactions contemplated hereby and by the Notes, the Note Purchase Agreement or the SecurityDocuments.     2. Except as set forth on Schedule II hereto or as expressly waived hereby, all of therepresentations, warranties, terms, covenants, conditions and other provisions of the Notes, theNote Purchase Agreement and the Security Documents shall remain unamended and unwaived and shallcontinue to be, and shall remain, in full force and effect in accordance with their respectiveterms. The amendment set forth herein shall be limited precisely as provided for herein to theprovisions expressly waived hereby and shall not be deemed to be an amendment to, waiver of,consent to, or modification of any other term or provision of the Notes, the Note PurchaseAgreement, the Security Documents or any other document referred to therein or herein or of anytransaction or further or future action on the part of the Company or any Guarantor that wouldrequire the consent of the Noteholders (or any subset thereof) under the Notes, the Note PurchaseAgreement or the Security Documents.     3. This Amendment is a document executed pursuant to the Notes and shall be construed,administered and applied in accordance with all of the terms and provisions of the Notes. Anybreach of any representation, warranty, covenant or agreement contained in this Amendment shall bedeemed to be an Event of Default for all purposes of the Notes, the Note Purchase Agreement and theSecurity Documents.     4. The Company hereby agrees that it will take any action that from time to time may bereasonably necessary to effectuate the agreements contemplated herein.     5. This Amendment may be executed in any number of separate counterparts, each of which, whenso executed, shall be deemed an original, and all of said counterparts taken together shall bedeemed to constitute but one and the same instrument     6. This Amendment shall be binding upon and inure to the benefit of the parties hereto andtheir respective successors and assigns.     7. This Amendment shall be construed in accordance with the internal laws of the State of NewYork without regard to the conflicts of laws provisions thereof. Each party hereto herebyirrevocably submits to the jurisdiction of any court of the State of New York located in the Countyof New York or the United States District Court for the Southern District of the State
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of New York, any appellate courts from any thereof (any such court, a “New YorkCourt”) or any court of the United Kingdom located in London, or any appellate courts from anythereof (any such court, a “U.K. Court”), for the purpose of any suit, action or otherproceeding arising out of or relating to this Amendment or under any applicable securities laws andarising out of the foregoing, which is brought by or against such party, and each such party herebyirrevocably agrees that all claims in respect of any such suit, action or proceeding will be heardand determined in any New York Court or U.K. Court. Each such party hereby agrees not to commenceany action, suit or proceeding relating to this Amendment other than in a New York Court except tothe extent mandated by applicable law. Each such party hereby waives any objection that it may nowor hereafter have to the venue of any such suit, action or proceeding in any such court or thatsuch suit, action or proceeding was brought in an inconvenient court and agree not to plead orclaim the same. EACH PARTY TO THIS AMENDMENT HEREBY EXPRESSLY WAIVES ANY RIGHT TO TRIAL BY JURY OFANY CLAIM, DEMAND, ACTION OR CAUSE OF ACTION ARISING UNDER THIS AMENDMENT OR IN ANY WAY CONNECTEDWITH OR RELATED OR INCIDENTAL TO THE DEALINGS OF THE PARTIES HERETO OR ANY OF THEM WITH RESPECTTHIS AMENDMENT, OR THE TRANSACTIONS RELATED HERETO, IN EACH CASE WHETHER NOW EXISTING OR HEREAFTERARISING, AND WHETHER FOUNDED IN CONTRACT OR TORT OR OTHERWISE; AND EACH PARTY HEREBY AGREES ANDCONSENTS THAT ANY SUCH CLAIM, DEMAND, ACTION OR CAUSE OF ACTION SHALL BE DECIDED BY COURT TRIALWITHOUT A JURY, AND THAT ANY PARTY TO THIS AMENDMENT AND CONSENT MAY FILE AN ORIGINAL COUNTERPARTOR A COPY OF THIS SECTION WITH ANY COURT AS WRITTEN EVIDENCE OF THE CONSENT OF THE SIGNATORIESHERETO TO THE AMENDMENT OF THEIR RIGHT TO TRIAL BY JURY.     8. If any one or more of the provisions contained in this Amendment shall, for any reason, beheld to be invalid, illegal or unenforceable in any respect, such invalidity, illegality orunenforceability shall not affect any other provisions of this Amendment and such provision shallbe interpreted to the fullest extent permitted by the law; *provided*that the Company and eachNoteholder shall use their reasonable best efforts to find and employ an alternative means toachieve the same or substantially the same result as that contemplated by such provision.[Remainder of Page Left Intentionally Blank]
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     IN WITNESS WHEREOF, the undersigned have caused this Amendment to be duly executed anddelivered as of the date first above written.      VIATEL HOLDING (BERMUDA) LIMITED