“Existing Credit Agreement” is defined in the first recital.ARTICLE IIAMENDMENTS TO EXISTING CREDIT AGREEMENT     SECTION 2.1. The Existing Credit Agreement is hereby amended as follows:     SECTION 2.1.1. Section 1.1 of the Existing Credit Agreement is hereby amended by inserting thefollowing definitions in the appropriate alphabetical order:     “Pittsburgh Sale” means the sale of some or all of the assets and liabilities of MitelTechnologies, Inc. (including certain customer contracts) which are located at, or related to, thebranch offices of Mitel Technologies, Inc. in Pittsburgh, Pennsylvania for consideration which mayinclude consideration other than cash.     “Third Amendment” means the Third Amendment to the Credit Agreement, dated as of July31, 2008, among the Borrowers and the Lenders party thereto.     “Third Amendment Effective Date” means the Amendment Effective Date as that term isdefined in the Third Amendment.     SECTION 2.1.2. Section 1.1 of the Existing Credit Agreement is hereby amended by amending andrestating the definition of Consolidated Working Capital Adjustment in its entirety to read asfollows:“Consolidated Working Capital Adjustment’ means, for any Fiscal Year, the amount(which may be a negative number) by which Consolidated Working Capital as of the end ofsuch Fiscal Year exceeds (or is less than) Consolidated Working Capital as of thebeginning of such Fiscal Year.”     SECTION 2.1.3. Section 7.2.11 of the Existing Credit Agreement is hereby amended by amendingand restating clause (d)(ii) thereof to read as follows: “the Net Disposition Proceeds receivedfrom such Disposition, together with the Net Disposition Proceeds of all other assets Disposed ofpursuant to this clause since the Closing Date, does not exceed (individually or in the aggregate)$15,000,000 over the term of this Agreement (it being understood that to the extent cash proceedsare received from the Pittsburgh Sale, such cash proceeds (but no other proceeds) shall be includedwhen calculating the amount of Dispositions pursuant to this clause (d)(ii))”     SECTION 2.1.4. Section 7.2.11 of the Existing Credit Agreement is hereby amended by (a)deleting the word “or” at the end of clause (d) thereof, (b) replacing the period (“.”) at the endof clause (e) thereof with “; or” and inserting a new clause (f) which shall read: “(f) thePittsburgh Sale.”
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ARTICLE IIICONDITIONS TO EFFECTIVENESS     SECTION 3.1. Conditions to Effectiveness. This Amendment shall become effective uponthe prior or simultaneous satisfaction of each of the following conditions in a manner reasonablysatisfactory to the U.S. Administrative Agent (the date when all such conditions are so satisfiedbeing the “Amendment Effective Date”):     SECTION 3.1.1. Counterparts. The U.S. Administrative Agent shall have received (i)counterparts to this Amendment, executed by the Borrowers and the Required Lenders and (ii) a fullyexecuted copy of an amendment to the Second Lien Credit Agreement, substantially in the form ofthis Amendment.     SECTION 3.1.2. Certificate of Authorized Officer. The Borrowers shall have delivered acertificate of Authorized Officers, solely in their capacity as Authorized Officers of theBorrowers, certifying that, both immediately before and after giving effect to the this Amendmenton the Amendment Effective Date, the statements set forth in Article IV hereof are true andcorrect.     SECTION 3.1.3. Obligor Acknowledgment and Consent. The Parent and each Obligor (otherthen the Borrowers) shall execute and deliver an Acknowledgment and Consent in substantially theform of Annex I hereto.     SECTION 3.1.4. Legal Matters. All legal matters incident to this Amendment shall besatisfactory to the U.S. Administrative Agent and its counsel.     SECTION 3.1.5. Payment of Expenses. The Borrowers shall have paid all reasonable fees,costs and expenses of the Agents in connection with the preparation, execution and delivery of thisAmendment and the administration of the Credit Agreement, including without limitation, thereasonable fees and disbursements of counsel to the U.S. Administrative Agent.ARTICLE IVREPRESENTATIONS AND WARRANTIES     To induce the Lenders to enter into this Amendment, the Borrowers represent and warrant to theLenders as set forth below:     SECTION 4.1. Representations and Warranties, No Event of Default. The representationsand warranties contained herein, in Article VI of the Credit Agreement and in each other LoanDocument, including any certificate or other writing delivered by or on behalf of any Obligor toany Secured Party in connection with this Amendment are true and correct in all material respectsboth immediately before and after giving effect to this Amendment (except that any representationand warranty expressly made as of a specific date shall be true and correct only as of suchspecific date), and both immediately before and after giving effect to this Amendment no Default orEvent of Default shall have occurred, assuming effectiveness of this Amendment, and be continuingor would result from this Amendment becoming effective in accordance with its terms.
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     SECTION 4.2. Due Authorization, Non-Contravention, etc. The execution, delivery andperformance by each Obligor of this Amendment, the Credit Agreement as amended hereby and each LoanDocument executed or to be executed by it are in each case within such Person’s powers, have beenduly authorized by all necessary action, and do not (a) contravene any (i) Obligor’s OrganicDocuments, (ii) court decree or order binding on or affecting any Obligor or (iii) law orgovernmental regulation binding on or affecting any Obligor; or (b) result in (i) or require thecreation or imposition of any Lien on any Obligor’s properties (except as permitted by the CreditAgreement) or (ii) a default under any material contractual restriction binding on or affecting anyObligor.     SECTION 4.3. Government Approval, Regulation, etc. No authorization or approval orother action by, and no notice to or filing with, any Governmental Authority or other Person (otherthan those that have been, or on the Amendment Effective Date will be, duly obtained or made andwhich are, or on the Amendment Effective Date will be, in full force and effect) is required forthe consummation of this Amendment or the Credit Agreement as amended hereby or the due execution,delivery or performance by any Obligor of this Amendment, the Credit Agreement as amended hereby orany Loan Document to which it is a party.     SECTION 4.4. Validity, etc. This Amendment, the Credit Agreement (as amended hereby)and each Loan Document to which any Obligor is a party constitutes the legal, valid and bindingobligations of such Obligor, enforceable against such Obligor in accordance with their respectiveterms (except, in any case, as such enforceability may be limited by applicable bankruptcy,insolvency, reorganization or similar laws affecting creditors’ rights generally and by principlesof equity).ARTICLE VCONTINUED EFFECTIVENESS OF CREDIT AGREEMENT     SECTION 5.1. Continued Effectiveness of Credit Agreement. Each Borrower hereby (a)confirms and agrees that each Loan Document to which it is a party is, and shall continue to be, infull force and effect and is hereby ratified and confirmed in all respects except that on and afterthe Amendment Effective Date all references in any such Loan Document to the “Credit Agreement,”“thereto,” “thereof,” “thereunder” or words of like import referring to the Credit Agreement shallmean the Credit Agreement as amended by this Amendment, and (b) confirms and agrees that to theextent that any such Loan Document purports to assign or pledge to the Collateral Agent, or grantto the Collateral Agent, a Lien on any collateral as security for the Obligations of the Borrowersfrom time to time existing in respect of the Credit Agreement and the Loan Documents, such pledge,assignment and/or grant of a Lien is ratified and confirmed in all respects.ARTICLE VIMISCELLANEOUS     SECTION 6.1. Counterparts. This Amendment may be executed by the parties hereto inseveral counterparts, each of which when executed and delivered shall be an original and all ofwhich shall constitute together one and the same agreement. Delivery of an executed counterpart ofa signature page to this Amendment by facsimile (or other electronic transmission) shall beeffective as delivery of a manually executed counterpart of this Amendment.
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     SECTION 6.2. Cross-References. References in this Amendment to any Article or Sectionare, unless otherwise specified, to such Article or Section of this Amendment.     SECTION 6.3. Governing Law. This Amendment shall be governed by, and construed inaccordance with, the internal laws of the State of New York.     SECTION 6.4. Loan Document Pursuant to Credit Agreement. This Amendment constitutes a“Loan Document” under the Credit Agreement. Accordingly, it shall be an Event of Default under theCredit Agreement if (a) any representation or warranty made by an Obligor under or in connectionwith this Amendment shall have been untrue, false or misleading in any material respect when made,or (b) an Obligor shall fail to perform or observe any term, covenant or agreement contained inthis Amendment.     SECTION 6.5. No Waiver. This Amendment is not, and shall not be deemed to be, a waiverof or consent to any Event of Default, event with which the giving of notice or lapse of time orboth may result in an Event of Default, or other non-compliance now existing or hereafter arisingunder the Credit Agreement and the other Loan Documents.     SECTION 6.6. Successors and Assigns. This Amendment shall be binding upon and inure tothe benefit of the parties hereto and their respective successors and assigns.     SECTION 6.7. Fees and Expenses. The Borrowers shall pay on demand all out-of-pocketcosts and expenses of the Agents in connection with the preparation, execution and delivery of thisAmendment, including without limitation, the reasonable fees and expenses and other reasonablecharges of legal counsel to the Agents.     SECTION 6.8. WAIVER OF JURY TRIAL. EACH PARTY HERETO HEREBY KNOWINGLY, VOLUNTARILY ANDINTENTIONALLY WAIVES TO THE FULLEST EXTENT PERMITTED BY LAW ANY RIGHTS THEY MAY HAVE TO A TRIAL BYJURY IN RESPECT OF ANY LITIGATION BASED HEREON, OR ARISING OUT OF, UNDER, OR IN CONNECTION WITH,EACH LOAN DOCUMENT, OR ANY COURSE OF CONDUCT, COURSE OF DEALING, STATEMENTS (WHETHER ORAL ORWRITTEN) OR ACTIONS OF SUCH PERSON IN CONNECTION THEREWITH. EACH BORROWER ACKNOWLEDGES AND AGREESTHAT IT HAS RECEIVED FULL AND SUFFICIENT CONSIDERATION FOR THIS PROVISION (AND EACH OTHER PROVISIONOF EACH OTHER LOAN DOCUMENT TO WHICH IT IS A PARTY) AND THAT THIS PROVISION IS A MATERIALINDUCEMENT FOR THE OTHER PARTIES ENTERING INTO THIS AMENDMENT. EACH PARTY HERETO CERTIFIES THAT NOREPRESENTATIVE, AGENT OR ATTORNEY OF ANY OTHER PARTY HAS REPRESENTED, EXPRESSLY OR OTHERWISE, THATSUCH OTHER PARTY WOULD NOT, IN THE EVENT OF LITIGATION, SEEK TO ENFORCE THE FOREGOING WAIVER.
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     IN WITNESS WHEREOF, the parties hereto have executed and delivered this Amendment as of thedate first above written.      MITEL NETWORKS CORPORATION