<Page>

                                                                    EXHIBIT 10.5

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 1 of 12



      THE SYMBOL '***' IS USED THROUGHOUT THIS EXHIBIT TO INDICATE THAT THE
PORTION HAS BEEN OMITTED AND FILED SEPARATELY WITH THE COMMISSION.

TO:                               FROM:

PF.Net Corp.                      AT&T Corp.
1800 Alexander Bell Drive         1200 Peachtree Street
4th Floor                         Room 09E30
Reston, VA  20191                 Atlanta, GA  30309
Attn:   Donald L. Branscome       Attn: Lynn O. Pardue


General Purchase Agreement Number 4569177 ("Agreement") between AT&T Corp.
("Company") and PF.Net, Corp. ("Supplier") dated October 29,1999 and as modified
by Amendment Nos. 1 and 2, is further modified by Amendment Number 3 as follows:


1.    ARTICLE 3: STATEMENT OF WORK FOR THE SUPPLY OF LINK(S): The following
      language is added to the Agreement as a new Section 3.1.N through 3.1.U:

       3.1.N  The Links referenced in Section 3.1.E. of the Agreement,
       Amendment 2, are modified to reflect the following:

            CHANGE THE LANGUAGE IN THE FIRST LINE:

                  FROM:       Links 37, 43 and 44

                  TO:         Links 37, 38 and 39

      3.1.O For Page 18, Link 20 of Exhibit B of the Agreement, Amendment 2, the
      Builder Substantially Complete Date and Builder Compete Date are modified
      as follows:

            BUILDER SUBSTANTIALLY COMPLETE DATE:

                  FROM:       January 31, 2001

                  TO:         March 31, 2001

            BUILDER COMPLETE DATE:

                  FROM:       July 31, 2001

                  TO:         September 30, 2001


<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 2 of 12


      3.1.P WASHINGTON, DC: On Link 38, the Builder is authorized by AT&T to add
      an additional AT&T POP location, hereinafter referred to as the
      "Washington DC-13th Street Addition" at no additional charge to AT&T. AT&T
      further authorizes Builder to add one (1) one and one-half (1 1/2") inch
      Conduit in addition to the three (3) Conduits already agreed upon to be
      installed, totaling four (4) Conduits, to the section of Link 38 between
      the Washington DC-13th Street Addition and the AT&T POP located at 30 East
      Street SW, Washington DC at no additional charge to AT&T. AT&T's credit
      due from Builder for the elimination of AT&T's requirement for land to
      build an Optical Amplifier at the Santa Ana, CA site has been offset fully
      by the Work to be done in this 3.1.P by Builder.

      3.1.Q CHARLOTTE TELSTAR, NC: On Link 37, the Builder is authorized by AT&T
      to delete the AT&T POP location known as Charlotte Telstar. This AT&T
      Charlotte Telstar POP deletion will be at no decrease in cost to AT&T as
      long as the Work outlined in Section 3.1.P above is completed by Builder
      according to the specifications in this Agreement.

      3.1.R LINK 43 AND LINK 44: AT&T and Builder mutually agree to cancel the
      respective obligations of each party for the following Links and as noted
      in Exhibit B:

            LINK 43: Chicago to Elkhart
            LINK 44:  Toledo to Cleveland

      AT&T will pay Builder the amount of forty percent (40%) of Builder's
      actual documented cost and expense which represents payment in full for
      services rendered prior to the date of termination. The parties agree to
      share ownership of the tangible work product developed prior to the date
      of termination and said work product includes but is not limited to the
      following: line list of tracts of land planned to be crossed by routes,
      engineering drawings, planned route maps, permit applications and permits
      granted, engineering notes and contact reports with permitting agencies
      and any other information which was obtained by the Builder and its
      subcontractors in conjunction with the contract to build these Links and
      is useful in proceeding with future construction of these Routes. AT&T
      shall make payment within thirty (30) days of the date of it's receipt of
      Builders invoice with costs documentation together with the tangible work
      product described herein but in no case prior to January 1, 2002.

      3.1.S REVISION OF LINK 12 PRICING:

      (a)   Builder and AT&T agree to modify the pricing for the construction of
            Link 12 as indicated in Exhibit B attached hereto. The pricing
            indicated in Exhibit B shall become effective immediately for all of
            this Link 12; however, AT&T will continue to pay the pre-Amendment
            #3 Exhibit B price through September 30, 2001, at which time the
            parties will calculate the difference in the price paid by AT&T and
            the price that has been in effect since the signing of this
            Amendment #3 and Builder will issue to AT&T a credit in that amount.
            The credit will be due

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 3 of 12


            to AT&T from Builder on or before 11/1/01. The revised pricing per
            mile for Link 12 shall be Thirty Seven Thousand Three Hundred
            Seventy Dollars ($37,370) per mile for the total of Link 12.

      (b)   AT&T authorizes Builder to supply and install three (3) AT&T
            Conduits in the city of Ft. Worth, TX, for one thousand seven
            hundred fifty (1,750) feet to provide a diverse routing for Link 12.
            The cost for these three (3) additional AT&T Conduits in the city of
            Ft. Worth will be at the fixed price of [***] with construction to
            be completed no later than March 31, 2002, or sooner, if practical;
            providing the city of Ft. Worth agrees to issue to Builder the
            necessary construction permits, including the resolution of any
            license issues with AT&T, if required for the construction permits.
            In the event, the required license and construction permits cannot
            be obtained from the city of Ft. Worth for the route mentioned in
            this Section 3.1.S(b), the parties agree to jointly seek a mutually
            agreed upon alternate route and its pricing.

3.1.T: LINK 4 (ORLANDO, FL TO MIAMI, FL) AND LINK 6 (ELLISVILLE, FL TO ORLANDO,
       FL):

      (a)   For Link 4, the Builder Substantially Complete Date and Builder
            Complete Date shall be modified as follows. It is acknowledged by
            the parties that the Builder Substantially Complete and Builder
            Complete Date for Link 6 remains unchanged.

                  BUILDER SUBSTANTIALLY COMPLETE DATE FOR LINK 4:

                  FROM:       June 30, 2002

                  TO:         September 30, 2002

                  BUILDER COMPLETE DATE FOR LINK 4:

                  FROM:       December 31, 2002

                  TO:         March 31, 2003

      (b)   The parties acknowledge that the construction of Links 4 and 6 are
            dependent upon an agreement with the Florida Turnpike ("FL TPK") to
            grant to AT&T adequate land rights for the construction of Links 4
            and 6 only. To date, AT&T and the FL TPK have reached a verbal
            agreement and are currently negotiating a contract with the FL TPK.
            The proposed contract will require that the FL TPK will grant
            adequate land rights for Links 4 and 6, and AT&T will be required to
            provide facilities as set forth in Exhibit B, Links 4A and 6A
            attached hereto. The Builder has agreed to construct these
            additional facilities provided by AT&T for the FL TPK at the prices,
            terms and conditions as set forth in this Amendment and Exhibit B.
            The parties acknowledge that as the contract with the FL TPK has not
            yet been finalized, AT&T and Builder agree to negotiate in good
            faith any required adjustments to the price, terms and conditions
            based

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 4 of 12


            on the final scope of work using the unit prices listed in "Table:
            Link 4A and 6A Modifications" below. Exhibit B, Links 4A and Link 6A
            contain a reasonable effort between the parties to reach an estimate
            of the work associated with the FL TPK as it is currently known to
            date.

      (c)   For Link 4 from Ft. Pierce to Miami, FL, AT&T will provide to the
            Builder fiber optic cable to be installed in an existing AT&T spare
            conduit located on the FL TPK between Ft. Pierce and the
            intersection with the Route 820 in West Hollywood, FL and on public
            ROW or AT&T ROW from the Route 820 location to AT&T's designated
            Miami POP as set forth in Exhibit B. Builder will verify the
            integrity for use of the existing Conduit, make repairs if required
            according to Article 3.1.T(h), and install the fiber optical cable
            for a cost of [***] per mile. If manholes, hand holes, and/or
            marking is required, pricing for these items will be pursuant to
            the Table set forth below. AT&T will provide to Builder an IRU for
            24 fibers in this section from Ft Pierce to Miami and Builder will
            provide to AT&T an IRU for 12 fibers in the section from Dallas to
            Tulsa currently under construction by Builder.

      (d)   If AT&T and the FL TPK fail to enter into a contract for the
            required land rights to construct Link 4 and/or Link 6 as set forth
            in Section 3.1.T(b) above by October 30, 2001, then one of the
            following two options will commence between the parties: (1) the
            parties may agree to negotiate a new schedule, prices, terms and
            conditions for the Link(s), 4 and/or 6, that was not covered by a
            contract with the FL TPK or (2) either party may terminate the
            respective obligations on the Link(s) not contracted with the FL
            TPK, and AT&T will pay Builder for Work completed on the terminated
            Link(s) up to the date of termination.

      (e)   LINKS 4A AND 6A FL TPK: The "Table: Link 4A and 6A Modifications"
            below itemizes the mutually agreed upon modifications to the prices,
            terms and conditions as further set forth in Exhibit B that will be
            in effect for Links 4 and/or 6 upon the completion of a contract
            between AT&T and FL TPK.


TABLE:  LINK 4A AND 6A MODIFICATIONS

<Table>
<Caption>

---------------------------------------------------------------------------------------------------------------

                SCOPE OF AMENDED WORK ASSOCIATED WITH AT&T AND FLORIDA TURNPIKE ROW AGREEMENT
---------------------------------------------------------------------------------------------------------------
                              LINK 6A: WILDWOOD TO WINDERMERE - FLORIDA TURNPIKE
---------------------------------------------------------------------------------------------------------------
                                                UNIT PRICE     QUANTITIES       PRICE ($)      LOCATION
                                                ($)
---------------------------------------------------------------------------------------------------------------
<S>                                                <C>              <C>         <C>            <C>
Coincident Placement of Second Cable
(provided by AT&T) in existing spare conduit                                                   Wildwood to
(in miles)                                          [***]            38          [***]         Windermere
---------------------------------------------------------------------------------------------------------------
Install Manholes for FTA at cable splice                                                       Wildwood to
points (per splice point)                           [***]            12          [***]         Windermere
---------------------------------------------------------------------------------------------------------------
Install Cable Location Markers for FTA @ 10                                                    Wildwood to
markers per mile (per mile)                         [***]            38          [***]         Windermere
---------------------------------------------------------------------------------------------------------------
TOTAL                                                                            [***]
---------------------------------------------------------------------------------------------------------------
</Table>

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 5 of 12

<Table>
<Caption>

---------------------------------------------------------------------------------------------------------------
                             LINK 4A: WINDERMERE TO FT. PIERCE - FLORIDA TURNPIKE
---------------------------------------------------------------------------------------------------------------
                                                  UNIT PRICE
                                                  ($)          QUANTITIES       PRICE ($)         LOCATION
---------------------------------------------------------------------------------------------------------------
<S>                                                <C>             <C>         <C>             <C>
Engineer Furnish & Install 2 Conduits for                                                      Windermere to
the exclusive use of the Florida Turnpike          [***]           115          [***]          Fort Pierce
---------------------------------------------------------------------------------------------------------------
Install a separate 24 fiber cable in 1 of
the two conduits provided to the Florida                                                       Windermere to
Turnpike for their exclusive use                   [***]           115          [***]          Fort Pierce
---------------------------------------------------------------------------------------------------------------
Engineer Furnish & Install Handhole boxes          [***]           115          [***]          Windermere to
                                                                                               Fort Pierce
---------------------------------------------------------------------------------------------------------------
Furnish and Install Cable location markers @                                                   Windermere to
10 markers per mile                                [***]           115          [***]          Fort Pierce
---------------------------------------------------------------------------------------------------------------
TOTAL                                                                           [***]
---------------------------------------------------------------------------------------------------------------
</Table>


      (f)   FOR LINK 4A--FL TPK: Builder agrees to install one (1) additional
            Conduit for a total of three (3) Conduits to be installed for AT&T
            on Link 4 between Windermere, FL and Ft. Pierce, FL at a cost of
            [***] per mile. In addition, Builder agrees to replace approximately
            one and two tenths (1.2) miles of missing spare Conduit at a fixed
            cost of [***] for the Work.

      (g)   PRICE PER MILE FOR LINKS 4 AND 6: Upon execution of an agreement
            between AT&T and the FL TKP, the prices in Exhibit B, Links 4 and 6
            shall be modified to be at a cost of Thirty Five Thousand Fifty
            Dollars ($35,050) per mile. The Work by Builder as set forth in
            this Article 3.1.T and the Table above are included in the new price
            of Thirty Five Thousand Fifty Dollars ($35,050) per mile.

      (h)   Regarding the Work that Builder will provide in accordance with this
            Agreement on existing AT&T Conduits, it is assumed by both parties
            that the Conduit provided by AT&T is whole and usable for the
            intended purpose of installing fiber optic cable. If during the
            construction, it is discovered by Builder that the AT&T existing
            Conduit is in need of repair, Builder shall proceed with such
            repairs at Builder's cost plus fifteen percent (15%). Builder will
            maintain such records and make such records available upon AT&T's
            request to substantiate the costs and repairs.

3.1.U LINK 37 (ATLANTA, GA TO GREENSBORO, NC):

      (a)   For the section of the Link between Charlotte, NC and Greensboro,
            NC, the parties have agreed to cancel construction as of July 1,
            2001. AT&T will pay Builder the amount of forty percent (40%)
            Builder's actual documented cost and expense which represents
            payment in full for services rendered prior to the date of
            termination. The parties agree to share ownership of the tangible
            work

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 6 of 12


            product developed prior to the date of termination and said work
            product includes but not limited to the following: line list of
            tracts of land planned to be crossed by routes, engineering
            drawings, planned route maps, permit applications and permits
            granted, engineering notes and contact reports with permitting
            agencies and any other information which was obtained by the Builder
            and its subcontractors in conjunction with the contract to build
            these Links and is useful in proceeding with future construction of
            these Routes. AT&T shall make payment within thirty (30) days of the
            date of its receipt of Builder's invoice with costs documentation
            together with the tangible work product described herein but in no
            case prior to January 1, 2002.

      (b)   The Builder shall place The Cable in a separate existing AT&T spare
            Conduit along the Charlotte to Greensboro section of Link 37.

      (c)   The Builder is granted the right by AT&T to construct up to three
            (3) additional Builder's Conduits contained in Link 37 between
            Charlotte to Greensboro as set forth in Exhibit B, and not included
            in the installation of Conduits prior to July 1, 2001. The Builder's
            rights to use the AT&T ROW shall be as provided as a license in the
            format of Exhibit K of the Agreement. During the term of the
            Agreement, if Builder chooses to proceed with the construction as
            set forth in this paragraph (c), and upon AT&T's written notice to
            Builder within sixty (60) days of notice of such Builder
            construction, then AT&T shall have the right to have Builder install
            one or more Conduits on this portion of Link 37 for AT&T's exclusive
            use at a price equal to the fraction of the Builder's total
            reasonable costs which are equal to the fraction of AT&T Conduits to
            the total number of Conduits to be installed by Builder.

2.    Article 3.6 (Regeneration Buildings, OP/AMP Space and Sites) of the
      Agreement is amended to add the following 3.6.A through 3.6.O for only
      those sites identified in "Exhibit 3B: Links and Optical Amplifier
      Locations". Section 3.6.A of this Amendment provides for construction
      services to be provided by Builder to AT&T. The Builder will design,
      construct and install OA buildings that will be approximately twelve feet
      (12') by thirty feet (30') outer dimensions with a total of three hundred
      square feet (300 sq. ft.) of floor space as specified in Exhibit 3A of
      this Amendment. These services are separate and distinct from the sharing
      of and reimbursement of costs described in the remainder of this
      Amendment.

      3.6.A SUPPLY OF OA BUILDINGS: Builder agrees to supply to AT&T new Optical
      Amplifier ("OA") buildings (the "Supplied Services") at the Builder sites
      identified in "Exhibit 3B: Links and Optical Amplifier Locations" (the
      "Shared Sites"). It is contemplated that the new AT&T OA buildings will
      share the slab on which the adjacent Builder buildings are or may be
      located. The Supplied Services to be supplied, in addition to the other
      elements described in Article 3.6.A through 3.6.O, includes but is not
      limited to the following:

            (i)   Planning, engineering, construction and placement of the OA
                  building specified in Exhibit 3A of this Amendment;

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 7 of 12


            (ii)  Supervision and inspection of the pre-fabricated buildings
                  during fabrication and installation of the OA buildings;

            (iii) Assurance that the pre-fabricated OA building supplied by
                  Builder will be in accordance with the drawings and
                  specifications as set forth in Exhibit 3A of this Amendment;

            (iv)  Arrangement and installation of cable conduit for connection
                  to the OA buildings;

            (v)   Necessary engineering and construction services for the
                  purpose of power and communication cables entering and passing
                  through Builder's main building to the AT&T building;

            (vi)  Support the installation of AT&T's cable locating devices and
                  isolation closure in the Builder main OA building and
                  connections to the appropriate equipment in the AT&T building;

      In return for these Supplied Services, AT&T will pay the Builder [***]
      for each OA site constructed by the Builder. All Builder invoices are due
      within thirty (30) days of construction completion and site acceptance by
      AT&T but in no event prior to January 1, 2002.

      Upon mutual agreement by AT&T and Builder, this Section 3.6A may be
      superceded by a separate Construction Services Agreement between the
      Builder and AT&T for the construction of OA sites which would include
      terms substantially similar to the terms described in this amended Section
      3.6.A.

      3.6 B OPTICAL AMPLIFIER SITES: Builder will convey to AT&T adequate land
      rights and space at the Shared Sites for the use and occupation of the OA
      buildings. In addition, Builder will obtain all necessary land use and
      construction permits for the installation of the OA buildings. The nature
      of the rights conveyed to AT&T for the use of the land will be, dependant
      on the nature of Builder's interest in the underlying real estate, either
      fee simple ownership, partial assignment of easement, sub-lease, license
      or such other right of use as permitted by the nature of Builder's
      underlying rights. The land for the OA sites (the OA Land Sites") will be
      provided by Builder so that AT&T will have the right of use (regardless of
      the nature of AT&T's interest in the land) for a period of time no less
      than a period of time equal to Builder's use of the adjacent property but
      no less than forty (40) years from the date of the Agreement. The OA Land
      Sites will be free of restrictive easements or other legal restrictions
      with respect to use so that each party's portion of the OA site can be
      configured in such a way so as to permit the parties the rights to erect
      the parties' building(s) with parking, access and landscaping necessary to
      accommodate each party's respective needs. In the event Builder is unable
      to obtain a permit, license, grant or other right of use from any
      governmental entity or agencies for renewable terms for a minimum of forty
      (40) years, then Builder will obtain the maximum term available by law or
      regulation. In addition to the respective rights and obligations of AT&T
      and Builder that are expressly set forth in

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 8 of 12


      this Amendment Number 3, "Exhibit P: General Terms and Conditions
      Associated with Land Rights of OA Buildings and Services Contract" of this
      Amendment and attached hereto sets forth additional rights and obligations
      of AT&T and Builder, respectively, with respect to the OA land rights and
      will be included in the documents of conveyance from Builder to AT&T to
      the extent necessary. AT&T and Builder agree that if modifications to
      Exhibit P are required this will be by mutual agreement of the parties.

      3.6.C ELECTRICAL POWER FOR OA SITES: After expiration of the three (3)
      year period in which items (i) through (v) of Section 3.6.O are provided
      by Builder at the fixed unit price, Builder will charge AT&T negotiated
      rates for electrical power and building services. AT&T will have the
      option at any time during the term of this Agreement to provide its own
      electrical power upon giving ninety (90) days written notice to Builder of
      AT&T's intention to provide its own power.

      3.6.D EXPANSION OF OA SITE FOR AT&T: To the extent the individual OA site
      layouts permit Builder to reasonably do so in accordance with Exhibit 3B,
      Builder will reserve for AT&T sufficient space and appropriate land
      right(s) for nine hundred square feet (900 sq. ft.) which will consist of
      three (3) additional three hundred square feet (300 sq. ft.) OA buildings
      on Builder's slab for future expansion. Such space reservation will be
      subject to the following condition. After all spaces other than the slab
      spaces reserved for AT&T are used by Builder or sold to third parties;
      Builder may market for sale or use for its own purposes the spaces
      reserved for AT&T only after first providing AT&T the opportunity to
      purchase the space(s) and/or land right(s) for the slab space from
      Builder. Builder shall supply upon request from AT&T additional OA
      buildings conforming to Specifications in Exhibit 3A, within ninety (90)
      days or another time frame mutually agreed upon between the parties at a
      price not to exceed [***] per square foot for a period of three (3) years
      and [***] per square foot for two (2) additional years. AT&T is herewith
      granted the right to purchase and install their own building compatible
      with the adjacent buildings and substantially conforming to the
      specification of Exhibit 3A should AT&T decide to do so.

      3.6.E The terms for the provision of the OA building and the slab space at
      each specified OA site are as follows:

            (i)   AT&T will own the three hundred square foot (300 sq. ft.) OA
                  building, but the land upon which it is constructed is
                  provided by Builder to AT&T through appropriate land rights as
                  set forth in Article 3.6.B of this Amendment to allow for the
                  continuous use, occupation and quiet enjoyment for a term of
                  no less than forty (40) years unless Builder's underlying land
                  rights can only be for a lesser term then Builder shall
                  provide a term for the maximum period of time permitted by
                  such rights.

            (ii)  AT&T will provide appropriate rights to Builder through the
                  AT&T OA building for all cable access through to the adjacent
                  buildings;

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 9 of 12


            (iii) AT&T and AT&T co-location customers will have unrestricted
                  rights of access and egress to its respective three hundred
                  square foot (300 sq. ft.) OA building as well as non-exclusive
                  rights of access to the OA site(s) by way of the access road
                  and pedestrian pathways.

      3.6.F AT&T's Conduits and The Cable will be brought into Builder's main OA
      building at each site. The Cable will be brought into the Optical Service
      Entry Panel ("OSEP") provided by Builder in Builder's main OA building.
      AT&T's Fibers in the outside cable will be spliced to the AT&T Fibers in
      the inside cable (going to the AT&T LGX via the inter-building fiber
      conduit ladder rack) from the OSEP. Builder will provide appropriate
      rights to AT&T for the purpose of installing and maintaining all cables
      (power and communications) which enter Builder's main building and
      pass-through the Builder main building to connect AT&T and its customers
      in the AT&T OA building. Adjacent to the OSEP will be adequate space to
      mount an isolation closure. The office ground will be extended to this
      location to tie into the isolation closure. Additionally, there will be
      adequate space provided by Builder for the mounting of relays provided by
      AT&T for the LMS cable locating system.

      3.6.G In the case of a commercial AC power failure, Builder shall notify
      the AT&T NOC that the commercial AC power has failed, and the status of
      the standby generator and the dispatch of personnel to the appropriate OA
      site. The status of the standby generator's fuel level and estimated
      balance of the run time shall also be communicated to the AT&T NOC. The
      Builder maintenance force shall contact the AT&T NOC to notify the AT&T
      NOC of any alarm indications that may affect AT&T. In the case of a
      failure of the standby generator to automatically start upon the loss of
      commercial AC, Builder shall be responsible for dispatching its
      maintenance personnel to the site to manually start the standby generator
      before the battery reserve is exhausted.

      3.6.H Builder will provide additional DC power, from one hundred eighty
      (180) Amps up to three hundred sixty (360) Amps no later than six (6)
      months from receipt of AT&T's written request for additional power
      conditioned upon the parties reaching mutually acceptable terms and
      conditions.

      3.6.I AT&T will confirm its requirement for power fusing in ten (10) Amp
      increments at acceptance of the OA building or AT&T will provide the
      Builder a minimum of sixty (60) days written notice prior to provision of
      such fusing unless the parties mutually agree upon a different notice
      period.

      3.6.J For an additional three (3) year period after the initial three (3)
      year period from acceptance by AT&T, AT&T will pay and Builder agrees to
      provide increments of ten (10) Amp fuse power at the rate of [***]
      per month per ten (10) Amps. After the six (6) year period, Builder and
      AT&T will mutually agree upon the ten (10) Amp fuse power incremental
      rate based on the average market price charged by other telecom
      co-location providers.

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 10 of 12


      3.6.K If at any time AT&T decides to relocate from the OA building(s)
      provided by the Builder, Builder shall assist AT&T at no cost to Builder
      with planned cable intrusions necessary to extend the AT&T fibers from the
      initial location supplied by Builder to a location on the an OA site owned
      by AT&T.

      3.6.L For those OA sites on the Links identified in Exhibit 3B, Builder
      shall be relieved of its obligation to provide a temporary road, clearing
      and permitting for that portion of the Sites to be conveyed to AT&T. It
      does not relieve Builder of its requirements to provide adequate access
      and egress as set forth in this Article 3.6.

      3.6.M Builder will obtain the right and assign the OA building warranty
      from Rohn to AT&T or in the event, if Builder is unable to assign the
      warranty an acceptable alternative to AT&T will be provided.

      3.6.N Builder will be prepared to provide additional OA buildings to AT&T
      up to ninety (90) day written notice. In the event there are circumstances
      that will restrict Builder's ability to provide such OA buildings, the
      parties will discuss alternate solutions to the mutual agreement of the
      parties. The price for each additional OA building beyond the number set
      forth in Exhibit 3B shall be mutually agreed upon between the parties at
      the time of the request by AT&T for additional OA buildings, however, the
      price for the OA building shall not exceed [***] per square foot including
      installation and associated Work for a period of three (3) years from the
      date of this Amendment and for an additional two (2) years thereafter, the
      price shall not exceed [***] per square foot including installation and
      associated Work. In the event the parties cannot agree upon pricing for
      additional OA buildings, AT&T has the right to acquire and install its own
      OA buildings, providing such buildings substantially equal and of the same
      design as the original OA buildings provided by the Builder.

      3.6.O In consideration of 3.6.B through 3.6.N, Builder will provide the
      following:

            (i)   For three (3) years from acceptance date, -48V DC power at no
                  additional charge to AT&T; AT&T may at its sole decision
                  utilize the Builder provided DC power or provide its own DC
                  power at it's own expense.

            (ii)  For three (3) years from acceptance date, up to one hundred
                  eighty (180) Amps continuous drain at no additional charge to
                  AT&T; provided, however, that should the total demand for
                  Amps, including demands made by AT&T, Builder and third
                  parties, exceed three hundred (300) Amps, AT&T will either
                  share in the cost, on mutually acceptable terms, to upgrade
                  Builder's power system or AT&T will provide its own power.

            (iii) For three (3) years from acceptance date, full building
                  services, including building alarm monitoring at no additional
                  charge to AT&T.

<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 11 of 12


            (iv)   Acquisition of land for the location of the OA buildings;
                   and

             (v)   Acquisition of all land use and construction permissions to
                   install the building.


3.    MODIFICATIONS TO EXHIBITS:

      A.    Exhibit B is deleted in its entirety and replaced with the modified
            Exhibit B attached hereto.

      B.    Exhibit 3A and 3B are hereby added to the Agreement and attached
            hereto.

      C.    Exhibit O: Exhibit O is deleted in its entirety and replaced with
            the modified Exhibit O attached hereto.

      D.    Exhibit P: General Terms and Conditions Associated with Land Rights
            of OA Buildings and Services Contract is hereby added to the
            Agreement and attached hereto.




             THE REMAINDER OF THIS PAGE IS INTENTIONALLY LEFT BLANK


<Page>

                                                           Agreement No. 4569177
                                                                 Amendment No. 3
                                                                   Page 12 of 12


This Amendment No. 3 is effective as of the execution of this Amendment by both
parties and shall be incorporated in and shall constitute a part of the
Agreement as if fully set forth therein. EXCEPT AS AMENDED HEREIN, ALL TERMS AND
CONDITIONS OF THE AGREEMENT REMAIN UNCHANGED.




APPROVAL:

ACKNOWLEDGED AND AGREED TO BY:



PF.NET CORP.                           AT&T CORP.


BY       /s/ Donald L. Branscome       BY      /s/ Diana L. Jones
         ----------------------------          ---------------------------------
         (signature)                           (signature)

NAME     DONALD L. BRANSCOME           NAME    DIANA L. JONES

         ----------------------------          ---------------------------------

TITLE    SENIOR VICE PRESIDENT -       TITLE   GROUP PROCUREMENT DIRECTOR,
         BUSINESS DEVELOPMENT                  AT&T SUPPLIER MANAGEMENT
         ----------------------------          ---------------------------------


DATE      July 27, 2001                DATE     July 25, 2001
         ----------------------------          ---------------------------------
         (typed or printed)                    (typed or printed)