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                            SUPPLEMENTAL INDENTURE

          SUPPLEMENTAL INDENTURE (this "Supplemental Indenture"), dated as of
August 2, 2000, among MID-ATLANTIC RMTS HOLDINGS, LLC (the "Guaranteeing
Subsidiary"), an indirect subsidiary of ONEPOINT COMMUNICATIONS CORP. (or its
permitted successor, a Delaware corporation (the "Company"), the Company, the
other Subsidiary Guarantors (as defined in the Indenture referred to herein) and
HARRIS TRUST AND SAVINGS BANK, as trustee under the indenture referred to below
(the "Trustee").

                         W  I  T  N  E  S  S  E  T  H

          WHEREAS, the Company has heretofore executed and delivered to the
Trustee an indenture (the "Indenture"), dated as of May 21, 1998 providing for
the issuance of an aggregate principal amount of up to $175,000,000 of 142%
Notes due 2008 (the "Notes");

          WHEREAS, the Indenture provides that under certain circumstances the
Guaranteeing Subsidiary shall execute and deliver to the Trustee a supplemental
indenture pursuant to which the Guaranteeing Subsidiary shall unconditionally
guarantee all of the Company's Obligations under the Notes and the Indenture on
the terms and conditions set forth herein (the "Subsidiary Guarantee"); and

          WHEREAS, pursuant to Section 9.01 of the Indenture, the Trustee is
authorized to execute and deliver this Supplemental Indenture.

          NOW THEREFORE, in consideration of the foregoing and for other good
and valuable consideration, the receipt of which is hereby acknowledged, the
Guaranteeing Subsidiary and the Trustee mutually covenant and agree for the
equal and ratable benefit of the Holders of the Notes as follows:

1. CAPITALIZED TERMS.  Capitalized terms used herein without definition shall
   have the meanings assigned to them in the Indenture.

2. AGREEMENT TO GUARANTEE.  The Guaranteeing Subsidiary hereby agrees as
   follows:

   (a)  Along with all Subsidiary Guarantors named in the Indenture, to jointly
        and severally Guarantee to each Holder of a Note authenticated and
        delivered by the Trustee and to the Trustee and its successors and
        assigns, irrespective of the validity and enforceability of the
        Indenture, the Notes or the obligations of the Company hereunder or
        thereunder, that:

        (i)    the principal of and interest on the Notes will be promptly paid
            in full when due, whether at maturity, by acceleration, redemption
            or otherwise, and interest on the overdue principal of and interest
            on the Notes, if any, if lawful, and all other obligations
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            of the Company to the Holders or the Trustee hereunder or thereunder
            will be promptly paid in full or performed, all in accordance with
            the terms hereof and thereof; and

     (ii)      in case of any extension of time of payment or renewal of any
          Notes or any of such other obligations, that same will be promptly
          paid in full when due or performed in accordance with the terms of the
          extension or renewal, whether at stated maturity, by acceleration or
          otherwise. Failing payment when due of any amount so guaranteed or any
          performance so guaranteed for whatever reason, the Subsidiary
          Guarantors shall be jointly and severally obligated to pay the same
          immediately.

(b)  The obligations hereunder shall be unconditional, irrespective of the
     validity, regularity or enforceability of the Notes or the Indenture, the
     absence of any action to enforce the same, any waiver of consent by any
     Holder of the Notes with respect to any provisions of the Indenture, this
     Supplemental Indenture or the Notes, the recovery of any judgment against
     the Company, any action to enforce the same or any other circumstances
     which might otherwise constitute a legal or equitable discharge or defense
     of a guarantor.

(c)  The following is hereby waived:  diligence presentment, demand of payment,
     filing of claims with a court in the event of insolvency or bankruptcy of
     the Company, any right to require a proceeding first against the Company,
     protect, notice and all demands whatsoever.

(d)  This Subsidiary Guarantee shall not be discharged except by complete
     performance of the obligations contained in the Notes and the Indenture.

(e)  If any Holder or the Trustee is required by any court or otherwise to
     return to the Company, the Subsidiary Guarantors, or any custodian,
     Trustee, liquidator or other similar official acting in relation to either
     the Company or the Subsidiary Guarantors, any amount paid by either to the
     Trustee or such Holder, this Subsidiary Guarantee, to the extent
     theretofore discharged, shall be reinstated in full force and effect.

(f)  The Guaranteeing Subsidiary shall not be entitled to any right of
     subrogation in relation to the Holders in respect of any obligations
     guaranteed hereby until payment in full of all obligations guaranteed
     hereby.

(g)  As between the Subsidiary Guarantors, on the one hand, and the Holders and
     the Trustee, on the other hand, (x) the maturity of the obligations
     guaranteed hereby may be accelerated as provided in Article 6 of the
     Indenture for the purposes of this Subsidiary Guarantee, notwithstanding
     any stay, injunction or other prohibition preventing such acceleration in
     respect of the obligations guaranteed hereby, and (y) in the event of any
     declaration of acceleration of such obligations as provided in Article 6 of
     the Indenture, such obligations (whether or not due and payable) shall
     forthwith become due and payable by the Subsidiary Guarantors for the
     purpose of this Subsidiary Guarantee.

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(h)     The Subsidiary Guarantors shall have the right to seek contribution from
        any non-paying Subsidiary Guarantors so long as the exercise of such
        right does not impair the rights of the Holders under the Subsidiary
        Guarantees.

(i)     Pursuant to Section 10.02 of the Indenture, after giving effect to any
        maximum amount and any other contingent and fixed liabilities that are
        relevant under any applicable Bankruptcy or fraudulent conveyance laws,
        and after giving effect to any collections from, rights to receive
        contribution from or payments made by or on behalf of any other
        Subsidiary Guarantor in respect of the obligations of such other
        Subsidiary Guarantor under Article 10 of the Indenture shall result in
        the obligations of such Subsidiary Guarantor under its Subsidiary
        Guarantee not constituting a fraudulent transfer or conveyance.

3. EXECUTION AND DELIVERY.  Each Guaranteeing Subsidiary agrees that the
   Subsidiary Guarantees shall remain in full force and effect notwithstanding
   any failure to endorse on each Note a notation of such Subsidiary Guarantee.

4. GUARANTEEING SUBSIDIARY MAY CONSOLIDATE, ETC. ON CERTAIN TERMS.

   (a)  The Guaranteeing Subsidiary may not consolidate with or merge with or
        into (whether or not such Guaranteeing Subsidiary is the surviving
        Person) another corporation, Person or entity whether or not affiliated
        with such Guaranteeing Subsidiary unless;

        (i)         subject to Section 10.05 of the Indenture, the Person formed
              by or surviving any such consolidation or merger (if other than a
              Subsidiary Guarantor or the Company) assumes all the obligations
              of such Subsidiary Guarantor, pursuant to a supplemental indenture
              in form and substance reasonably satisfactory to the Trustee,
              under the Notes, the Indenture, the Pledge Agreement and the
              Registration Rights Agreement on the terms set forth herein or
              therein; and

        (ii)        immediately after giving effect to such transaction, no
              Default or Event of Default exists.

        (iii)       except in the case of any such merger or consolidation with
              the Company or another Subsidiary Guarantor, the Company would, on
              a pro forma basis, immediately after giving effect to such
              transaction, be permitted to incur at least $1.00 of additional
              Indebtedness pursuant to the Debt to Cash Flow Ratio test set
              forth in Section 4.09 of the Indenture.

              In case of any such consolidation, merger, sale or conveyance and
              upon the assumption by the successor Person, by supplemental
              indenture, executed and delivered to the Trustee and satisfactory
              in form to the Trustee, of the Subsidiary Guarantee endorsed upon
              the Notes and the due and punctual performance of all of the
              covenants and conditions of the Indenture to be performed by the
              Subsidiary Guarantor, such successor

                                      -3-
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          Person shall succeed to and be substituted for the Subsidiary
          Guarantor with the same effect as if it had been named as a Subsidiary
          Guarantor. Such successor Person thereupon may cause to be signed any
          or all of the Subsidiary Guarantees to be endorsed upon all of the
          Notes issuable under the Indenture which theretofore shall not have
          been signed by the Company and delivered to the Trustee. All the
          Subsidiary Guarantees so issued shall in all respects have the same
          legal rank and benefit under the Indenture as the Subsidiary
          Guarantees theretofore and thereafter issued in accordance with the
          terms of the Indenture as though all of such Subsidiary Guarantees had
          been issued at the date of the execution of the Indenture.

          Except as set forth in Articles 4 and 5 of the Indenture, and
          notwithstanding clauses (i) and (ii) above, nothing contained in this
          Supplemental Indenture, the Indenture or in any of the Notes shall
          prevent any consolidation or merger of a Subsidiary Guarantor with or
          into the Company or another Subsidiary Guarantor, or shall prevent any
          sale or conveyance of the property of a Subsidiary Guarantor as an
          entirety or substantially as an entirety to the Company or another
          Subsidiary Guarantor.

(b)    In case of such consolidation, merger, sale or conveyance and upon the
       assumption by the successor Person, by supplemental indenture, executed
       and delivered to the Trustee and satisfactory in form to the Trustee, of
       the Subsidiary Guarantee endorsed upon the Notes and the due and punctual
       performance of all of the covenants and conditions of the Indenture to be
       performed by the Subsidiary Guarantor, such successor Person shall
       succeed to and be substituted for the Subsidiary Guarantor. Such
       successor Person thereupon may cause to be signed any or all of the
       Subsidiary Guarantees to be endorsed upon all of the Notes issuable
       hereunder which theretofore shall not have been signed by the Company and
       delivered to the Trustee. All the Subsidiary Guarantees so issued shall
       in all respects have the same legal rank and benefit under the Indenture
       as the Subsidiary Guarantees theretofore and thereafter issued in
       accordance with the terms of the Indenture as though all of such
       Subsidiary Guarantees had been issued at the date of the execution
       hereof.

(c)    Except as set forth in Articles 4 and 5 of the Indenture, and
       notwithstanding clauses (a) and (b) above, nothing contained in the
       Indenture or in any of the Notes shall prevent any consolidation or
       merger of a Subsidiary Guarantor with or into the Company or another
       Subsidiary Guarantor, or shall prevent any sale or conveyance of the
       property of a Subsidiary Guarantor as an entirety or substantially as an
       entirety to the Company or another Subsidiary Guarantor.

5. RELEASES.

   (a) In the event of a sale or other disposition of all of the assets of any
       Subsidiary Guarantor, by way of merger, consolidation or otherwise, or a
       sale or other disposition of all to the capital stock of any Subsidiary
       Guarantor, then such Subsidiary Guarantor (in the event of a sale or
       other disposition, by way of merger, consolidation or otherwise, of all
       of the capital stock

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         of such Subsidiary Guarantor) or the Person acquiring the property (in
         the event of a sale or other disposition of all or substantially all of
         the assets of such Subsidiary Guarantor) will be released and relieved
         of any obligations under its Subsidiary Guarantee; provided that the
         Net Proceeds of such sale or other disposition are applied in
         accordance with the applicable provisions of the Indenture, including
         without limitation Section 4.10 of the Indenture. Upon delivery by the
         Company to the Trustee of an Officers' Certificate and an Opinion of
         Counsel to the effect that such sale or other disposition was made by
         the Company in accordance with the provisions of the Indenture,
         including without limitation Section 4.10 of the Indenture, the Trustee
         shall execute any documents reasonably required in order to evidence
         the release of any Subsidiary Guarantor from its obligations under its
         Subsidiary Guarantee.

     (b) Any Subsidiary Guarantor not released from its obligations under its
         Subsidiary Guarantee shall remain liable for the full amount of
         principal of and interest on the Notes and for the other obligations of
         any Subsidiary Guarantor under the Indenture as provided in Article 10
         of the Indenture.

6.   NO RECOURSE AGAINST OTHERS. No past, present or future director, officer,
     employee, incorporator, stockholder or agent of the Guaranteeing
     Subsidiary, as such, shall have any liability for any obligations of the
     Company or any Guaranteeing Subsidiary under the Notes, any Subsidiary
     Guarantees, the Indenture or this Supplemental Indenture or for any claim
     based on, in respect of, or by reason of, such obligations or their
     creation. Each Holder of the Notes by accepting a Note waives and releases
     all such liability. The waiver and release are part of the consideration
     for issuance of the Notes and the Subsidiary Guarantees. Such waiver may
     not be effective to waive liabilities under the federal securities laws and
     its is the view of the Commission that such a waiver is against public
     policy.

7.   NEW YORK LAW TO GOVERN. THE INTERNAL LAW OF THE STATE OF NEW YORK SHALL
     GOVERN AND BE USED TO CONSTRUE THIS SUPPLEMENTAL INDENTURE BUT WITHOUT
     GIVING EFFECT TO APPLICABLE PRINCIPLES OF CONFLICTS OF LAW TO THE EXTENT
     THAT THE APPLICATION OF THE LAWS OF ANOTHER JURISDICTION WOULD BE REQUIRED
     THEREBY.

8.   COUNTERPARTS.  The parties may sign any number of copies of this
     Supplemental Indenture. Each signed copy shall be an original, but all of
     them together represent the same agreement.

9.   EFFECT OF HEADINGS.  The Section headings herein are for convenience only
     and shall not affect the construction hereof.

10.  THE TRUSTEE.  The Trustee shall not be responsible in any manner whatsoever
     for or in respect of the validity of this Supplemental Indenture or for or
     in respect of the recitals contained herein, all of which recitals are made
     solely by the Guaranteeing Subsidiary and the Company.

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          IN WITNESS WHEREOF, the parties hereto have caused this Supplemental
Indenture to be duly executed and attested, all as of the date first above
written.


DATED:  August 2, 2000


                              MID-ATLANTIC RMTS HOLDINGS, LLC


                              By:__________________________________________
                              Name:________________________________________
                              Title:_______________________________________


                              ONEPOINT COMMUNICATIONS CORP.


                              By:__________________________________________
                              Name:________________________________________
                              Title:_______________________________________



                              HARRIS TRUST AND SAVINGS BANK, as Trustee


                              By:__________________________________________
                              Name:________________________________________
                              Title:_______________________________________
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                                  SCHEDULE I
                                  ----------

                       SCHEDULE OF SUBSIDIARY GUARANTORS

          The following schedule lists each Subsidiary Guarantor under the
Indenture as of August 2, 2000:

          OnePoint Communications Holdings, LLC

          OnePoint Communications - Georgia, LLC

          OnePoint Communications - Illinois, LLC

          OnePoint Communications - Colorado, LLC

          VIC-RMTS-DC, LLC

          OnePoint Services, L.L.C.

          RCP Communications, Inc.

          Mid-Atlantic RMTS Holdings, LLC