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                                                                  Exhibit 10.1.3

                                  BAKER CENTER
                            FIRST AMENDMENT OF LEASE

DATE:       September 5, 1996

BETWEEN:    ST. PAUL PROPERTIES, INC.
            435 Peavey Building
            730 Second Avenue South
            Minneapolis, MN 55402                           ("Landlord")

AND:        ADVANCED TELECOMMUNICATIONS, INC.
            410 Peavey Building
            730 Second Avenue South
            Minneapolis, MN 55402                           ("Tenant")

IN RESPECT OF PREMISES IN:       Peavey Building

LANDLORD AND TENANT hereby agree as follows:

1.    In this Amendment of Lease:

      (a)   "Building" means Peavey Building located in the city of Minneapolis

      (b)   "Premises" means 3,737 square feet of space on the fourth floor of
            the Building, as set out in the Lease.

      (c)   "Lease" means the lease between Landlord and Tenant dated August 14,
            1996, covering the Premises.

      (d)   "Amendment Date" means the 4th day of September, 1 996.

2.    Effective on the Amendment Date, the following is added as Article 27.00:

      ARTICLE 27.00 SECURITY DEPOSIT

      27.01 Security Deposit Tenant shall deposit with Landlord, the sum of Five
            Thousand Six Hundred and Five Dollars and no/100 ($5,605.00), (the
            "Security Deposit"), on or before the date of full execution of this
            Lease. The Security Deposit shall be held by Landlord, without
            interest


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            thereon, as security for the full and faithful performance by Tenant
            of each and every term, covenant and condition of this Lease to be
            observed and performed by Tenant. The Security Deposit shall not be
            mortgaged, assigned, transferred or encumbered by Tenant and any
            such act on the part of Tenant shall be null and void and of no
            force and effect. If any Rent or any other sum payable by Tenant to
            Landlord shall be unpaid or should Tenant fail to perform any of the
            terms of this Lease, then Landlord may, and without prejudice to any
            other remedy, appropriate and apply the Security Deposit to
            compensate Landlord toward they payment of the Rent or other sums
            due from Tenant, or towards any loss, damage or expense sustained by
            Landlord resulting from such default; and, in such event, Tenant
            shall forthwith restore the Security Deposit to the original sum
            required to be deposited. In the event Tenant shall fully and
            faithfully comply with all of the terms, covenants and conditions of
            this Lease, the Security deposit shill be returned in full to Tenant
            following the date of the expiration of the Lease Term and the
            surrender of the Premises by Tenant in compliance with the
            provisions of this Lease. In the event any bankruptcy, insolvency,
            reorganization or other creditor-debtor proceedings shall be
            instituted by or against Tenant, or its successors or assigns, such
            Security Deposit shall be deemed to be applied first to the payment
            of any rents and/or other charges due Landlord for all periods prior
            to institution of such proceedings and the balance, if any, of such
            Security Deposit may be Security Deposit to the purchaser or other
            transferee of Landlord's interest in the Premises and thereupon
            Landlord shall be discharged and released from all further liability
            with respect to such Security Deposit, and Tenant agrees to look
            solely to the new landlord or other transferee for the return of
            said Security Deposit. No holder of mortgage or deed of trust or
            lessor under a ground or underlying lease to which this Lease is or
            may be superior or subordinate shall be responsible in connection
            with the Security Deposit, unless such mortgagee or holder of such
            deed of trust or lessor shall have actually received the Security
            Deposit as such.

Except as specifically provided herein, the terms and conditions of the Lease
are confirmed and continued in full force and effect.

This Amendment of Lease shall be binding on the heirs, administrators,
successors and assigns (as the case may be) of the parties hereto.


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IN WITNESS OF THIS LEASE Landlord and Tenant have properly executed it as of the
date set out on page one.

LANDLORD:                                    TENANT:

ST. PAUL PROPERTIES, INC.                    Advanced Telecommunications, Inc.

By: /s/ R. William Inserra                   By: /s/ Michael A. Donahue
    -------------------------------              -------------------------------
         R. William Inserra
    Vice President Asset Management          Its: Treasurer

9/10-96                                      Michael A. Donahue
-----------------------------------          -----------------------------------
Date Executed                                Please Type Signature

                                             9/5/96
                                             -----------------------------------
                                             Date Executed

                                             -----------------------------------
                                             Witness to the signature of Tenant
                                             if not incorporated.


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