<PAGE>

                            June 1, 1999 Amendment
                                    to the
       Agreement and Plan of Reorganization between Netco Communications
 Corporation, Netco Acquiring Corporation, FreeMail, Inc., Glenn Kreisel, Steve
Saroff, Chris Coyle, Steve Barrett, Greg Gianforte, Ray Kreisel and William
Knight

WAMINET Inc. (f/k/a Netco Communications Corporation) ("The Company") Netco
Acquiring Corporation ("NAC"), FreeMail, Inc., Glenn Kreisel, Steve Saroff,
Chris Coyle, Steve Barrett, Greg Gianforte, Ray Kreisel and William Knight and
FreeMail, Inc. are parties to an Agreement and Plan of Reorganization dated
December 18, 1997 (the "Agreement").

       It is agreed between the parties that Section 1.3(b) of the Agreement be
amended to read:

(b)    Additional Contingent Consideration
       -----------------------------------

(i)    Subject to the terms of this Section 1.3(b), and subject to The Company's
       and NAC's right of offset as described in Section 8.3 below, The Company
       shall pay to the Shareholders the additional contingent consideration
       ("Additional Contingent Consideration") as, and not to exceed the total
       amount, provided in this Section 1.3(b).

(ii)   Commencing the third quarter 1999, the Company shall pay allocably to the
       Shareholders as Additional Contingent Consideration an aggregate
       quarterly sum (the "Quarterly Payment") equal to five percent (5%) of the
       gross collected revenue derived by the Company during the applicable
       period.

(iii)  The Quarterly Payment shall be allocated among the Shareholders ratably
       to their receipt of The Company common shares according to Schedule
       1.3(a) to this Agreement.

(iv)   The total amount of Quarterly Payments payable by The Company in
       accordance with this Section 1.3(b) shall not exceed Two Million Dollars
       ($2,000,000.00) in value payable as follows: the first one million
       dollars shall be paid in cash; thereafter quarterly payments shall be
       made by the issuance of Company shares valued, in the alternative, by the
       then current market value if said shares are publicly traded or, if
       private, valued in accordance with the last sale of the Company's shares
       in an investment transaction. For purposes of this valuation an
       investment transaction is an arms length transaction with a third party
       in an amount material to the Company. As an example, the most recent such
       valuation arises from the transaction between WAMINET and SGI, which
       valued the stock at a price of $11.38 per share calculated on a fully-
       diluted basis.

(v)    The Quarterly Payments will be made within thirty (30) days following the
       end of each calendar quarter, the first payment is due after the third
       quarter of 1999. At
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     the time of each Quarterly Payment, The Company shall furnish to a duly
     appointed representative selected by majority of the Shareholders a
     financial statement showing the gross collected revenue derived by the
     Company during the applicable period. The duly appointed representative of
     a majority of the Shareholders, or their agent and/or accountant shall have
     the right, exercisable no more often than once each year, to examine The
     Company's records during normal business hours, upon ten day's prior
     written notice, to confirm the adequacy and accuracy of the Quarterly
     Payments and of related quarterly financial statements since the then most
     recent of the last such examination, or twenty four(24) months. The Company
     shall promptly pay any deficiency revealed by such examination together
     with simple interest at the rate of eight percent (8%) per annum from date
     on which any such deficient amounts first became payable through the date
     of payment. In addition, if such deficiencies exceed five percent (5%) of
     the total amount owned for the period to which the examination relates, The
     Company shall also pay all reasonable costs and expenses incurred by the
     Shareholders, and by their duly appointed representative, in the conduct of
     such examination.

IN WITNESS WHEREOF, the parties hereto have duly executed the amendment.


Date: 6/28/99                      WAM!NET Inc.


                                   /s/ Edward J. Driscoll
                                   --------------------------------



                                   Glenn Kreisel

Date: 6/21/99                      /s/ Glenn Kreisel
                                   --------------------------------


                                   Steve Saroff

Date: 6/21/99                      /s/ Steve Saroff
                                   --------------------------------



Date: June 21st 1999               Ray Kreisel

                                   /s/ Ray Kreisel
                                   --------------------------------


Date: 6/21/99                      William Knight

                                   /s/ William Knight
                                   --------------------------------
<PAGE>

Date: 6/22/99                           Steve Barrett

                                        /s/ Steve Barrett
                                        --------------------------

Date: 6/22/99                           Greg Gianforte

                                        /s/ Greg Gianforte
                                        --------------------------

Date: 6/22/99                           Chris Coyle

                                        /s/ Chris Coyle
                                        --------------------------