Exhibit 10-dd

THIRD AMENDMENT TO  PARTICIPATION AGREEMENT AND LEASE

THIS THIRD AMENDMENT TO PARTICIPATION AGREEMENT AND LEASE, dated as of October 31, 2001 (this " Amendment"), amends (i) 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") and (B) the Second Amendment to Participation Agreement, dated as of August 24, 2001 (the " Second Amendment") (as so amended by the First Amendment and the Second Amendment, the " Participation Agreement") and (ii) the Lease, dated as of
October 22, 1999 between ADC, as Lessee and Mortgagor, and the Agent Lessor, as Agent Lessor and Mortgagee (the " Lease"). 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, the Lease and the other Operative Documents to fund the Construction of the Financed Improvements on the Land;
and

WHEREAS,
the parties hereto desire to amend the Participation Agreement and the Lease as hereinafter set forth;

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 3, (a) the Participation Agreement shall be amended in
accordance with Sections 1.1through 1.22and (b) the Lease shall be amended in accordance with Sections 1.23through 1.25.

SECTION
1.1 Advance Dates. Section 3.1 of the Participation Agreement is hereby amended to add the following at the end of the initial sentence of the final paragraph thereof:



SECTION
1.2 Certificates. Section 3.7 of the Participation Agreement is hereby amended by adding the following sentence at the end thereof:



SECTION
1.3 Amounts Due Under Lease. Clause (iii) of Section 5.2 of the Participation Agreement is hereby amended by replacing the reference to "Construction Recourse" thereof with the reference to
"Residual Guarantee".

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SECTION
1.4 Distribution. Clause (iii) of Section 5.3(b) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



SECTION
1.5 Distribution. Clause (iv) of Section 5.3(b) of the Participation Agreement and the paragraphs following such clause (iv) are hereby amended and restated in their
entirety to read as follows:



SECTION
1.6 Distribution. Section 5.3(c) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



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SECTION
1.7 Distribution. Section 5.3(d) of the Participation Agreement is hereby amended and restated in its entirety to read as follows:



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SECTION
1.8 Distribution. Subclause (ii) of clause third of Section 5.3(f) of the Participation Agreement is hereby amended by adding immediately after the reference to " Section 5.3(c)" therein the following: "(but excluding clausethirdfrom the application thereof)".

SECTION
1.9 Distribution. Section 5.3 of the Participation Agreement is hereby amended by adding thereto immediately following clause (f) thereof the following new clause (g):



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SECTION
1.10 Distribution. Section 5.4 of the Participation Agreement is hereby amended by adding a new Section 5.4(c), which shall read as follows:



SECTION
1.11 Application of Amounts. The Participation Agreement is hereby amended by adding immediately after Section 5.4 thereof the following new Section 5.5:



SECTION
1.12 Representations of the Participants. Section 7.1(b) of the Participation Agreement is hereby amended by adding immediately after the reference to "Such Participant" therein the following:
"(other than the
Tranche ADC Participant)".

SECTION
1.13 Covenants of the Lessee. The last sentence of Section 8.1(b) of the Participation Agreement is hereby amended by adding immediately after the reference to "fixtures or equipment" at the end
of
such sentence the following:



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SECTION
1.14 Enhancer Collateral. The Participation Agreement is hereby amended by adding immediately after Section 8.19 thereof the following new Section 8.20:



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SECTION
1.15 The Participation Agreement is hereby amended by adding immediately after Section 8.20 thereof the following new Section 8.21:

"SECTION
8.21 Rent Prepayment; ADC Certificate.



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SECTION
1.16 Appointment; Powers.



SECTION
1.17 Actions Upon Instruction.



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SECTION
1.18 Separate Agent Lessor. Section 16.8 of the Participation Agreement is hereby amended by (a) adding to the first sentence thereof immediately after each of the three references to
"Collateral" therein the phrase "or Pledged Collateral", (b) adding to the fourth sentence thereof immediately after the reference to "Collateral" therein the phrase "or Pledged Collateral",
and (c) adding to the last sentence thereof immediately after the reference to "Collateral" therein the phrase "or Pledged Collateral".

SECTION
1.19 Termination of Agency. Section 16.9 of the Participation Agreement is hereby amended by adding immediately after the reference to "Collateral" therein the phrase "and Pledged Collateral".

SECTION
1.20 Limitations. Section 16.11 of the Participation Agreement is hereby amended by (a) adding immediately after the reference to "Collateral" in clause (b) thereof the
phrase "and Pledged Collateral" and (b) adding immediately after the reference to "Collateral" in clause (e) thereof the phrase "and Pledged Collateral, as the case may be,".

SECTION
1.21 Participants' Commitments; Address for Notices; Exhibit N.



SECTION
1.22 Definitions.



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SECTION
1.23 Certain Duties and Responsibilities of Agent Lessor. Section 7.3 of the Lease is hereby amended by adding immediately after the reference to "Collateral" therein the phrase "or the Pledged
Collateral".

SECTION
1.24 Lease Events of Default. Section 16.1(h) of the Lease is hereby amended by (a) replacing the period at the end of clause (h) thereof with "; or" and (b) adding immediately
after clause (h) thereof the following new clause (i):



SECTION
1.25 Lease Remedies. Section 16.2 of the Lease is hereby amended by (a) deleting the "or" at the end of clause (g) thereof, (b) replacing the period at the end of
clause (h) thereof with "; or" and (c) adding immediately after clause (h) thereof the following new clause (i):



SECTION
2. AMENDMENT FEE. Lessee agrees to pay to the Administrative Agent on the date hereof for the pro-rata benefit of the Participants an amendment fee (the " Amendment Fee") in an amount equal to
$150,000.

SECTION
3. 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
4. REPRESENTATIONS AND WARRANTIES. Each of the parties hereto hereby represents and warrants that (a) the execution, delivery and performance of each Third Amendment

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Document to which it is a party has been duly authorized by such party, (b) the person executing each Third Amendment Document to which it is a party on its behalf has been duly authorized to
act on its behalf, (c) each Third 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 Third Amendment
Document to which it is a party will not violate any agreement, law, rule or regulation 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 Third 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 Third 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 Third Amendment Document and (iv) the Agent Lessor (for the benefit of the Secured Parties) has a valid and enforceable first priority Lien on and security
interest in the Pledged Collateral (as defined in Section 1.22(n)hereof) free and clear of all other Liens.

SECTION
5. MISCELLANEOUS.

SECTION
5.1 Continuing Effectiveness, etc. This Amendment shall be deemed to be an amendment to the Participation Agreement and the Lease, and the Participation Agreement and the Lease, as amended hereby, and
each
other Operative Document, shall remain in full force and effect and are hereby ratified, approved and confirmed in each and every respect. On and after the date hereof, all references to the
"Participation Agreement" and the "Lease" in the Operative Documents or in any other document, instrument, certificate, agreement, opinion or writing shall be deemed to refer to the Participation
Agreement and the Lease, as the case may be, as amended hereby. Except as expressly set forth herein, the execution, delivery and effectiveness of this Amendment shall not operate as an amendment,
modification or waiver of any provision of, or any right, power or remedy of any party hereto under, any Operative Document.

SECTION
5.2 Severability. Any provision of this Amendment which is prohibited or unenforceable in any jurisdiction shall, as to such provision and such jurisdiction, be ineffective to the extent of
such prohibition or unenforceability
without invalidating the remaining provisions of this Amendment or affecting the validity or enforceability of such provision in any other jurisdiction.

SECTION
5.3 Headings. The various headings of this Amendment are inserted for convenience of reference only and shall not affect the meaning or interpretation of this Amendment or any provisions
hereof.

SECTION
5.4 Execution in Counterparts. This Amendment may be executed by the parties hereto in several counterparts, each of which shall be deemed to be an original and all of which shall constitute together
but
one and the same agreement.

SECTION
5.5 Governing Law. THIS AMENDMENT SHALL IN ALL RESPECTS BE GOVERNED BY THE INTERNAL LAW OF THE STATE OF NEW YORK AS TO ALL MATTERS OF CONSTRUCTION, VALIDITY AND PERFORMANCE, WITHOUT REGARD TO
CONFLICTS OF LAW PRINCIPLES, EXCEPT TITLE 14 OF ARTICLE 5 OF THE NEW YORK GENERAL OBLIGATIONS LAW. This Amendment constitutes the entire understanding among the parties hereto with respect to the
subject matter hereof and supersedes any prior agreement, written or oral, with respect thereto.

SECTION
5.6 Successors and Assigns. This Amendment shall be binding upon and shall inure to the benefit of the parties hereto and their respective successors and permitted assigns.

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SECTION
5.7 Fees and Expenses. Lessee agrees to pay on demand all costs and expenses of or incurred by each of the other parties hereto in connection with the negotiation, preparation, execution and
delivery of each Third Amendment Document, including the fees and expenses of counsel for the Agent Lessor, as well as all recording and filing fees and taxes with respect to the filings and
recordings made pursuant to Section 3(j)hereof.

[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:                                 
| |  |                                        

S-1

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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:                                                                                                                                               
| |  |                                                                                                                                                      

S-2

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| |  | AMSTERDAM FUNDING CORPORATION, as a Participant
| |  | -----------------------------------------------
| |  | By:                                            
| |  |                                                
| |  | Name:                                          
| |  |                                                
| |  | Title:                                         
| |  |                                                

S-3

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

S-4

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