Exhibit 10-ff

FIFTH AMENDMENT TO  PARTICIPATION AGREEMENT

THIS FIFTH AMENDMENT TO PARTICIPATION AGREEMENT, dated as of December 31, 2001 (this " Amendment"), amends the Participation
Agreement, dated as of October 22, 1999, by and among ADC Telecommunications, Inc., a Minnesota corporation (" ADC" or " Lessee"), as
Lessee; Lease Plan North America, Inc., not in its individual capacity, except as expressly stated therein, but solely as Agent Lessor for the Participants (the " Agent Lessor"); the Persons
named on Schedule I thereto, as Participants; and ABN AMRO Bank N.V., as Administrative Agent, as amended by (A) the First Amendment to
Participation Agreement, dated as of January 29, 2001 (the " First Amendment"), (B) the Second Amendment to Participation Agreement, dated as of August 24, 2001 (the " Second Amendment"), (C) the Third Amendment to the Participation Agreement and Lease, dated as of October 31, 2001 (the " Third Amendment") and
(D) the Fourth Amendment to the Participation Agreement and Lease, dated as of December 11, 2001 (the " Fourth Amendment") (as so amended by the First Amendment, the Second Amendment, the
Third Amendment and the Fourth Amendment, the " Participation Agreement"). Capitalized terms used herein and not otherwise defined herein shall have the respective meanings assigned thereto in
Appendix 1 to the Participation Agreement.

WHEREAS,
the parties hereto have entered into the Participation Agreement and the other Operative Documents to fund the Construction of the Financed Improvements on the Land;

WHEREAS,
prior to the date of this Amendment, the Put Event and Base Term Commencement Date have occurred;

WHEREAS,
the parties hereto desire to amend the Participation Agreement as hereinafter set forth, including to amend certain existing covenants and create new affirmative covenants of
Lessee and to set forth the applicable margins with respect to the calculation of Basic Rent;

NOW,
THEREFORE, in consideration of the premises and for other good and valuable consideration (the receipt and sufficiency of which are hereby acknowledged), the parties hereto agree as
follows:

SECTION
1. AMENDMENTS. Effective as of the date hereof and subject to the satisfaction of the conditions precedent set forth in Section 2, the Participation Agreement shall be amended in accordance with Sections 1.1through 1.16.

SECTION
1.1 Fees. Section 4.1(b)(ii) of the Participation Agreement is hereby amended by deleting the second paragraph in its entirety.

SECTION
1.2 Fees. Section 4.1 of the Participation Agreement is hereby amended by adding a new clause (vi), which shall read as follows:



SECTION
1.3 Fees. Section 4.1 of the Participation Agreement is hereby amended by adding a new clause (vii), which shall read as follows:



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SECTION
1.4 Limitation on Liens. Section 8.2(j) of the Participation Agreement is hereby amended by adding immediately after the reference to "permitted hereunder" the following:



SECTION
1.5 Limitation on Liens. Section 8.2(k) of the Participation Agreement is hereby amended and restated in its entirety as follows:



SECTION
1.6 Limitation on Liens. Section 8.2 of the Participation Agreement is hereby amended by deleting clause (l) in its entirety.

SECTION
1.7 Limitation on Liens. Section 8.2 of the Participation Agreement is hereby amended by adding the following paragraph immediately after clause (k) thereof:



SECTION
1.8 Restricted Payments. Section 8.11 of the Participation Agreement is hereby amended by adding immediately after the reference to "Lessee and any Wholly-Owned Subsidiary may" the following:
", with respect to the following clauses (a), (b) and (c) below, and any Wholly-Owned

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Subsidiary may, with respect to clause (d) below," and (B) amending and restating clause (c) in its entirety as follows:



SECTION
1.9 Restricted Payments. Section 8.11 of the Participation Agreement is hereby amended by (A) deleting the period at the end of clause (c) thereof and replacing it with ";" and
(B) adding the following new clause (d) immediately after clause (c) thereof:



SECTION
1.10 Net Worth. Section 8.17 of the Participation Agreement is hereby amended and restated in its entirety as follows:



SECTION
1.11 Funded Debt; Funded Debt to EBITDA Ratio. Section 8.18 of the Participation Agreement is hereby amended and restated in its entirety as follows:



|Fiscal Quarter                             |  | Amount
|------------------------------------------ |  | ------
|The Fiscal Quarter ending January 31, 2002 |  | $     
|The Fiscal Quarter ending April 30, 2002   |  | $     
|The Fiscal Quarter ending July 31, 2002    |  | $     
|The Fiscal Quarter ending October 31, 2002 |  | $     



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|Fiscal Quarter                                                                                                   |  | Ratio
|---------------------------------------------------------------------------------------------------------------- |  | -----
|The Fiscal Quarter ending January 31, 2003                                                                       |  | 5.0:1
|The Fiscal Quarter ending April 30, 2003                                                                         |  | 4.0:1
|The Fiscal Quarter ending July 31, 2003                                                                          |  | 3.5:1
|The Fiscal Quarter ending October 31, 2003                                                                       |  | 3.5:1
|Commencing with the Fiscal Quarter ending on January 31, 2004 and as of the end of any Fiscal Quarter thereafter |  | 3.0:1

SECTION
1.12 EBITDA; EBITDA to Interest Expense Ratio. Section 8.19 of the Participation Agreement is hereby amended and restated in its entirety as follows:



|Period                                                                                                                                                                      |  | EBITDA Amount |            
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | ------------- | -----------
|For the two consecutive Fiscal Quarters ending on April 30, 2002                                                                                                            |  | $             | (35,000,000
|For the three consecutive Fiscal Quarters ending on July 31, 2002                                                                                                           |  | $             | (8,000,000 
|For the four consecutive Fiscal Quarters ending on October 31, 2002                                                                                                         |  | $             | 58,000,000 
|For the four consecutive Fiscal Quarters ending on January 31, 2003                                                                                                         |  | $             | 98,000,000 
|For the four consecutive Fiscal Quarters ending on April 30, 2003                                                                                                           |  | $             | 136,000,000
|For the four consecutive Fiscal Quarters ending on July 31, 2003                                                                                                            |  | $             | 153,000,000
|For the four consecutive Fiscal Quarters ending on October 31, 2003 and for the four consecutive Fiscal Quarters ending as of the last day of any Fiscal Quarter thereafter |  | $             | 147,000,000



|Period                                                                                                                                                                |  | Ratio
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------- |  | -----
|The four consecutive Fiscal Quarters ending on January 31, 2003                                                                                                       |  | 3:0:1
|The four consecutive Fiscal Quarters ending on April 30, 2003 and for the four consecutive Fiscal Quarters ending as of the last day of any Fiscal Quarter thereafter |  | 4:0:1

SECTION
1.13 Enhancer Collateral. Section 8.20 of the Participation Agreement is hereby amended by adding immediately after clause (b) thereof the following new clause (c):



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SECTION
1.14 The Participation Agreement is hereby amended by adding immediately after Section 8.21 thereof the following new Section 8.22:

"SECTION
8.22 Asset Collateral.



SECTION
1.15 The Participation Agreement is hereby amended by adding immediately after Section 8.22 thereof the following new Section 8.23:



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SECTION
1.16 Definitions.



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" Transferred Assets" shall have such meaning as is given in the definition of "Receivables Financing" herein.

" Uncollateralized Participant Balance" means, with respect to each Benefited Participant as of any date of determination, an amount equal to (i) such Benefited Participant's outstanding
Participant Balance
on such date minus(ii) the portion of any Additional Enhancer Collateral (or proceeds thereof) pledged by Lessee to Agent Lessor pursuant to Section 8.20(c) of the Participation
Agreement which is distributable to such Benefited Participant following the occurrence of an Event of Default to reduce such Benefited Participant's Participant Balance pursuant to Section 5.3
of the Participation Agreement, as calculated by the Administrative Agent.

" Wholly Owned Subsidiary" means any Subsidiary of Lessee of which all of the equity securities or other ownership interests (other than, in the case of a corporation, directors' qualifying shares) are
so owned or controlled.

SECTION
2. CONDITIONS PRECEDENT. This Amendment shall become effective as of the date hereof upon the satisfaction of each of the following conditions precedent:



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SECTION
3. REPRESENTATIONS AND WARRANTIES.

Each
of the parties hereto hereby represents and warrants that, as of the date hereof, (A) the execution, delivery and performance of each Fifth Amendment Document to which it is
a party has been duly authorized by such party, (B) the person executing each Fifth Amendment Document to which it is a party on its behalf has been duly authorized to act on its behalf,
(C) each Fifth Amendment Document to which it is a party constitutes its legal, valid, binding and enforceable agreement, except as enforceability may be limited by bankruptcy, insolvency,
reorganization, moratorium or other laws or equitable principles relating to or limiting the rights of creditors generally, and (D) its entry into each Fifth Amendment Document to which it is a
party will not violate any law, rule or regulation or constitute a default under any material agreement by which it is bound or by which any of its assets are affected. In order to induce the
Participants and the Agent Lessor to execute and deliver each Fifth Amendment Document to which it is a party, Lessee hereby represents to each of the Participants and the Agent Lessor that, as of the
date hereof, (i) the representations and warranties set forth in Section 7.2 of the Participation Agreement are and shall be and remain true and correct, (ii) Lessee is in full
compliance with all of the terms and conditions of each Operative Document and Fifth Amendment Document to which it is a party, (iii) no Default or Event of Default has occurred and is
continuing or shall result after giving effect to each Fifth Amendment Document, (iv) the fair market value of the Asset Collateral consisting of intangible and tangible assets located outside
of the United States does not exceed 35%of Lessee's Net Worth and (v) the fair market value of the Asset Collateral consisting of intangible and tangible assets located within the United States
but which are assets owned by any entity whose jurisdiction of origin is outside the United States does not exceed 2%of Lessee's Net Worth. ABN AMRO BANK N.V., and Lease Plan North
America, Inc. each represent that, together, they represent the Required Participants.

SECTION
4. COVENANTS. The Lessee hereby covenants and agrees to, promptly after the Fifth Amendment Effective Date, request that Wachovia Bank, N.A. as agent and Blue Ridge Asset Funding
Corporation amend that certain Receivables Purchase Agreement dated as of December 12, 2001, as amended, to permit (i) ADC Telecommunications Sales, Inc. to pledge the stock of
ADC Receivables Corp. I and (ii) ADC Telecommunications Sales, Inc. and ADC DSL Systems, Inc. to pledge the subordinated notes issued by ADC Receivables Corp. I held by each, to
the Agent Lessor to secure the Lessee's obligations under this Agreement with such pledges to become effective on the Asset Collateralization Date. Lessee also covenants and agrees to cooperate fully
in Lessor's effort to enter into an intercreditor agreement with Wachovia Bank, N.A. and Blue Ridge Asset Funding Corporation in connection with such pledges. Upon request of Administrative Agent or
Agent Lessor, Lessee covenants and agrees to request similar consents in form and substance reasonably satisfactory to Administrative Agent and Agent Lessor to permit the pledge to Agent Lessor of the
stock or equity interest and any similar note with respect to any other Receivables Financing SPE or Receivables Financings and to fully cooperate with any intercreditor agreements.

SECTION
5. MISCELLANEOUS.



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[signature
pages follow]

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IN WITNESS WHEREOF, the parties hereto have caused this Amendment to be executed by their respective officers thereunto duly authorized as of the day and year first above written.

| |  | ADC TELECOMMUNICATIONS, INC., as Lessee
| |  | ---------------------------------------
| |  | By:                                    
| |  | Name:                                  
| |  |                                        
| |  | Title:                                 
| |  |                                        

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| |  | LEASE PLAN NORTH AMERICA, INC., not in its individual capacity, except as expressly stated in the Participation Agreement, but solely as Agent Lessor
| |  | -----------------------------------------------------------------------------------------------------------------------------------------------------
| |  | By:                                                                                                                                                  
| |  | Name:                                                                                                                                                
| |  |                                                                                                                                                      
| |  | Title:                                                                                                                                               
| |  |                                                                                                                                                      

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| |  | ABN AMRO BANK N.V., as Administrative Agent and as a Participant
| |  | ----------------------------------------------------------------
| |  | By:                                                             
| |  | Name:                                                           
| |  |                                                                 
| |  | Title:                                                          
| |  |                                                                 
| |  | By:                                                             
| |  | Name:                                                           
| |  |                                                                 
| |  | Title:                                                          
| |  |                                                                 

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