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                                                                   EXHIBIT 10.24

THIS NOTE HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED,
AND MAY NOT BE SOLD OR OTHERWISE TRANSFERRED WITHOUT THE PRIOR WRITTEN CONSENT
OF THE COMPANY.

THIS INSTRUMENT MAY BE SUBJECT TO CERTAIN SUBORDINATION PROVISIONS, AS FROM TIME
TO TIME IN EFFECT, BY AND AMONG THE OBLIGOR HEREUNDER AND CERTAIN OTHER PARTIES
THERETO, WHICH, AMONG OTHER THINGS, SUBORDINATE THE OBLIGATIONS OF THE OBLIGOR
HEREUNDER TO THE PRIOR PAYMENT OF CERTAIN OBLIGATIONS OF THE OBLIGOR TO THE
HOLDERS OF SENIOR INDEBTEDNESS AS DEFINED THEREIN.  IN ADDITION, THE RIGHTS OF
THE HOLDER HEREUNDER, INCLUDING THE RIGHT TO RECEIVE PAYMENT OF THE PRINCIPAL OF
AND INTEREST, IF ANY, ON THIS NOTE, ARE SUBJECT TO SET OFF IN ACCORDANCE WITH
SECTION 8.1(f) OF THE MEMBERSHIP SHARE PURCHASE AGREEMENT DATED AS OF MAY 14,
1999 BY AND AMONG THE COMPANY, ZEFER CORP. NORTHEAST, SPYPLANE LLC AND THE
EQUITYHOLDERS OF SPYPLANE LLC (THE "PURCHASE AGREEMENT").

                                 NONNEGOTIABLE
                                 -------------
                         SUBORDINATED PROMISSORY NOTE
                         ----------------------------

     FOR VALUE RECEIVED, the undersigned, ZEFER Corp., a Delaware corporation
(the "Company"), hereby promises to pay to Greg Hipwell, the principal amount of
Four Hundred Ninety Thousand Dollars ($490,000) on May 14, 2001, together with
interest from the date hereof on the principal amount from time to time unpaid
at a rate which shall at all times equal eight percent (8%) per annum; provided,
                                                                       --------
however, that said interest shall not accrue or be due or payable by the Company
-------
with respect to any amounts which the Company has properly set off pursuant to
Section 8.1(f) of the Purchase Agreement.  The Company shall make annual
payments in the amount of 50% of the unpaid interest hereunder, such payments
being made in arrears commencing on May 14, 2000.

     All payments to the holder hereof shall be made payable to Greg Hipwell,
123 Guerrero Street, Apartment 2, San Francisco, CA 94103.

     This Subordinated Promissory Note is nonnegotiable.  This Subordinated
                                          -------------
Promissary Note may not be sold, hypothecated, pledged, assigned or otherwise
transferred without the prior written consent of the Company.  On May 14, 2000,
the Company shall prepay $90,000 of the outstanding principal amount of this
Subordinated Promissory Note.  Notwithstanding the foregoing sentence, the
Company may at any time or from time to time prepay all or any part of the
outstanding principal amount of this Subordinated Promissory Note, without
penalty or premium, together with all accrued and unpaid interest in respect
thereof accrued to the date of prepayment.
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    If any one or more of the following events (herein termed "Events of
Default") shall happen, that is to say:

     (i) The Company shall fail to make any payment in respect of principal of
or interest on this Subordinated Promissory Note as the same shall become due,
whether by acceleration or otherwise, which failure shall continue for a period
of 15 days; or

     (ii) The Company shall:

          (A) commence a voluntary case under Title 11 of the United States Code
          as from time to time in effect, or authorize the commencement of such
          a voluntary case;

          (B) have filed against it a petition commencing an involuntary case
          under said Title 11 which shall not have been dismissed within 30 days
          after the date on which such petition is filed;

          (C) seek relief as a debtor under any applicable law, other than said
          Title 11, of any jurisdiction relating to the liquidation or
          reorganization of debtors or to the modification or alteration of the
          rights of creditors, or consent to or acquiesce in such relief;

          (D) have entered against it an order by a court of competent
          jurisdiction (1) finding it to be bankrupt or insolvent, (2) ordering
          or approving its liquidation, reorganization or any modification or
          alteration of the rights of its creditors, or (3) assuming custody of,
          or appointing a receiver or other custodian for all or a substantial
          part of its property;

          (E) make an assignment for the benefit of, or enter into a composition
          with, its creditors, or appoint or consent to the appointment of a
          receiver or other custodian for all or a substantial part of its
          property; or

          (F) sell all or substantially all of its assets or there shall be a
          transfer of more than 51% of the Company's equity interests to an
          entity not currently a holder of equity interests of the Company;

then and in each and every such case, subject to the terms of any subordination
agreement or provisions by and among the Company and the holder hereof, the
holder of this note may by notice in writing to the Company declare all or any
part of the unpaid balance of the principal of and interest on this Subordinated
Promissory Note then outstanding to be forthwith due and payable, and thereupon
such unpaid balance or part thereof shall become so due and payable without
presentation, protest or further demand or notice of any kind, all of which are
hereby expressly waived, and the holder of this note may proceed to enforce
payment of such balance or part thereof in such manner as the holder of this
note may elect.
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     No failure by the holder to take action with respect to any Event of
Default shall affect its subsequent rights to take action with respect to the
same or any other Event of Default.

     This Subordinated Promissory Note shall be governed by and construed in
accordance with the laws (other than the conflict of law rules) of The
Commonwealth of Massachusetts.

     The Company and all endorsers and guarantors hereby waive presentment,
demand, notice, protest and all other demands and notices in connection with the
delivery, acceptance, performance and enforcement of this Subordinated
Promissory Note, except as specifically otherwise provided in this Subordinated
Promissory Note, and assent to extensions of time of payment, or forbearance or
other indulgence without notice.

     The holder of this Subordinated Promissory Note is hereby on notice that
the right to receive payment of the principal of or interest on this
Subordinated Promissory Note is subject to the Company's rights of set off in
accordance with Section 8.1(f) of the Purchase Agreement.  Exercise of such
rights of set off by the Company under the Purchase Agreement shall not
constitute an event of default hereunder.  In addition, the holder of this
Subordinated Promissory Note agrees that, upon the request of the Company, such
holder shall execute a subordination agreement requested by any senior lender of
the Company, which subordination agreement may provide, among other things, that
the indebtedness evidenced by this Subordinated Promissory Note and the payment
by the Company of the principal hereof and interest hereon shall be subordinate
to and junior in right of payment to the prior payment in full of all "Senior
Indebtedness" (or other equivalent term) as defined therein.

                        *     *     *     *     *     *

                                       3
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IN WITNESS WHEREOF, the undersigned has caused this Subordinated Promissory Note
to be executed by its duly authorized officer as of May 14, 1999.

                                       ZEFER CORP.

                                       By: /s/ Sean W. Mullaney
                                          ----------------------------------
                                          Name:  Sean W. Mullaney
                                          Title:  Secretary

                                       4<PAGE>
                                                                   EXHIBIT 10.25

                     FLOATING RATE LOAN-PROCEDURES LETTER
                     ------------------------------------

Harris Trust and Savings Bank
111 West Monroe Street
Chicago, Illinois 60690

Gentlemen:

     ZEFER CORP., a Delaware corporation (the "Company") hereby requests that
borrowings under its $20,000,000 revolving line of credit granted by Harris
Trust and Savings Bank be made and documented upon the following terms and
conditions. You agree until further notice that upon oral advice by telephone
received by you from time to time from authorized persons listed in this letter
that we wish to borrow money, you will lend and deposit to such accounts from
time to time as specified by our written direction (the "Amount") such sums of
money as may be mutually agreed upon. We agree to confirm such borrowings in
writing by mailing on the same day a letter in the form attached hereto as
Exhibit A signed by any one of the following officers:

                                Deirdre Aubuchon
                                Sean Mullaney
                                Phillip Canfield
                                Timothy McAdam

It is understood, however, that pending receipt of such letter by you in
the ordinary course of the mails, that any sums of money borrowed by telephone
on advice of an authorized person or a person purporting to be an authorized
person in accordance with the foregoing arrangement shall immediately be
credited to the Account, and we shall be obligated to repay to you the sums so
borrowed at the time and with the interest set forth in this letter
notwithstanding that any such borrowing is not confirmed as contemplated above.

     All such borrowings shall be repaid by us upon your demand, but they may,
at our election in any instance, be repaid at any time upon telephonic advice to
you.

     All borrowings made by us under our line of credit from you shall bear
interest prior to maturity at the rate per annum which is equal to the rate per
annum which is equal at all times to the rate from time to time announced by you
as your prime commercial rate, with any change in the interest rate on such
borrowings by virtue of a change in such prime commercial rate to be and become
effective as of and on the date of this relevant change in such prime commercial
rate. Interest shall be computed on the basis of a year of 360 days and actual
days elapsed and shall be payable on the last day of each month and upon demand.

     All borrowings hereunder shall be made against and evidenced by a
promissory note of the Company payable to your order in the aggregate principal
amount of $20,000,000, such note to mature as set forth in, and to be
otherwise in the form of Exhibit B attached hereto (the "Note"). You agree that
notwithstanding the fact that the Note is in the principal amount of
$20,000,000, it shall evidence only the actual principal amount of borrowings
made by us from time to time under our line of credit from you and you agree
that if you transfer or assign the Note you will stamp thereon a statement of
the actual principal amount evidenced thereby at the time of transfer. We agree
that in any action or proceeding instituted to collect or enforce collection of
the Note, the amount shown as owing you on your records shall be prima facie
evidence of the unpaid balance of principal and interest on the Note.

                                       1
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     The officers authorized to give you telephonic instructions to lend money
and repay borrowings in accordance with the foregoing are:

                                Phillip Canfield
                                Timothy McAdam
                                Deirdre Aubuchon
                                Sean Mullaney

In accepting telephonic advice from any of such officers and/or employees in
accordance with the terms of this Agreement, you shall be entitled to rely on
advice given by any person purporting to be any one of such officers and shall
have no liability to us on account of any action taken by you pursuant to such
telephonic advice provided you have acted in good faith in connection therewith.
You are, of course, authorized to lend money to us upon the written instructions
of any officers and/or employees authorized to borrow funds by telephonic
advice.

     This Procedures Letter and the arrangements and authorizations herein
contemplated shall remain in full force and effect, and shall be applicable to
any renewals of, or replacements or substitutions for, our present revolving
line of credit from you, unless and until you have received written notice from
the Company of the termination or modification of this Procedures Letter at your
office in Chicago, Illinois or unless and until the Company has received such a
notice at its address as shown on your records from you; provided that no such
termination or modification by the Company shall affect any transaction which
occurred prior to the receipt of such notice by you nor shall any such
termination or modification become effective without your written consent unless
and until all amounts which shall have been borrowed hereunder shall have been
repaid in full. This Procedures Letter and your acceptance of this Procedures
Letter as hereinafter contemplated do not constitute any commitment on your part
to make any credit available to the Company, it being understood that the making
of credit available to the Company by you from time to time shall be under and
pursuant to the revolving line of credit arrangement that this Company has with
you and shall be subject to the terms and conditions incidental to such
revolving line of credit. This Procedures Letter and the rights and remedies of
the parties hereto shall be governed by the laws of Illinois.

     If you are in agreement with the foregoing, please sign in the appropriate
place on the enclosed counterpart and return such counterpart to us, whereupon
this letter shall become a binding agreement between you and us.

     Dated as of this 16th day of July, 1999.

                                                   Very truly yours,

                                                   ZEFER CORP.

                                                   By: /s/ Sean W. Mullaney
                                                      ---------------------
                                                      Its: Vice President
                                                          ---------------

     Accepted as of the date last above written.
                                                   HARRIS TRUST AND SAVINGS BANK

                                                   By:  /s/ John M. Dillon
                                                      ---------------------
                                                      John M. Dillon
                                                      Its: Vice President

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