Document:

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                                                                   Exhibit 10.24

                                PROMISSORY NOTE
                       SECURED BY STOCK PLEDGE AGREEMENT

         NOTICE: THIS PROMISSORY NOTE PROVIDES FOR A BALLOON PAYMENT.

$409,962.00                              San Mateo, California
                                         January 14, 2000

     For value received, the undersigned, Robert H. Ewald ("Borrower"), promises
to pay to E-STAMP CORPORATION, a Delaware corporation ("E-Stamp"), or order, at
2855 Campus Drive, San Mateo CA 94403, or such other place as E-Stamp may
designate in writing from time to time, in lawful money of the United States of
America, without abatement, demand, deduction, setoff or counterclaim, the
principal sum of Four Hundred Nine Thousand Nine Hundred Sixty-two and 00/100
Dollars ($409,962.00), together with interest thereon at the rate of five and
eighty-eight hundredths percent (5.88%) per annum, compounded annually, from the
date first set forth above until all outstanding principal, accrued interest and
other charges under this Promissory Note are paid in full.

     1.   Payments.  All outstanding principal and accrued interest under this
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Promissory Note shall be due and payable on the Due Date (as defined below);
provided, however, that so long as Borrower is an officer of E-Stamp, Borrower's
obligation to pay principal and interest under this Promissory Note shall be
forgiven as follows: (a) principal in the amount of Fifty-one Thousand Two
Hundred Forty-five and 25/100 Dollars ($51,245.25) shall be forgiven as of the
date first set forth above, and (b) principal in the amount of Fifty-one
Thousand Two Hundred Forty-five and 25/100 Dollars ($51,245.25), plus accrued
but unpaid interest on the outstanding balance of principal hereunder, shall be
forgiven on February 18, 2000, May 18, 2000, August 18, 2000, November 18, 2000,
February 18, 2001, May 18, 2001 and August 18, 2001.  Notwithstanding the
preceding to the contrary, if Borrower sells any of the Pledged Collateral (as
defined below), the outstanding principal and accrued interest under this
Promissory Note shall be due and payable to the extent of the gross sales price,
less commissions, derived from the sale of the Pledged Collateral.  Every
payment received by E-Stamp with respect to this Promissory Note shall be
applied as follows: first, to the payment of any late charges; second, to the
payment of accrued but unpaid interest; and, third, to the payment of the
outstanding principal balance of this Promissory Note.

     2.   Due Date.  The "Due Date" shall be the earlier of (i) the date that
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Borrower ceases to be an officer of E-Stamp, whether voluntarily or
involuntarily, and whether with or without cause, or (ii) August 18, 2001.

     3.   Purpose of Loan.  Borrower acknowledges and agrees that E-Stamp is
          ---------------
making this loan to Borrower for the purpose of financing Borrower's income and
payroll tax liability associated with the issuance to Borrower of 100,000 shares
of E-Stamp common stock on August 18, 1999.

     4.   Default.  In the event that Borrower fails to pay any amount due under
          -------
this Promissory Note as and when due or to timely perform any other obligation
of Borrower under this Promissory Note and/or the Pledge Agreement (as defined
below), E-Stamp may, at its option, declare the entire principal sum and all
accrued but unpaid interest under this Promissory Note immediately due and
payable.  In the event that E-Stamp exercises this option or the principal
balance of this Promissory Note otherwise becomes due and payable, all principal
then outstanding under this Promissory Note shall thereafter bear simple
interest at the lesser of ten percent (10%) per annum or the maximum rate
permitted by law.  Failure to exercise this option shall not constitute a waiver
of E-Stamp's right to exercise the same with respect to any prior or subsequent
defaults.

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     5.   Security.  Borrower's obligations under this Promissory Note are
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secured by that certain Stock Pledge Agreement of even date herewith ("Pledge
Agreement") encumbering 60,000 shares of common stock of E-Stamp owned by
Borrower and pledged as collateral thereunder ("Pledged Collateral").

     6.   Full Recourse Loan.  This Promissory Note evidences a full recourse
          ------------------
loan.  Borrower acknowledges that Borrower is personally liable for the
performance of the obligations of Borrower under this Promissory Note, and
Borrower's liability shall not be limited to the value of the Pledged Collateral
or other security provided to E-Stamp to secure Borrower's performance of its
obligations under this Promissory Note.

     7.   Tax Liability.  Borrower understands and agrees that any and all
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income and payroll tax liability to Borrower resulting from this Promissory
Note, including, without limitation, the forgiveness of principal and interest
hereunder, shall be the sole responsibility of Borrower.

     8.   Attorneys' Fees.  In the event any legal action or proceeding is
          ---------------
required to enforce or interpret any provision of this Promissory Note, Borrower
shall pay to E-Stamp upon demand all costs of collection and reasonable
attorneys' fees incurred by E-Stamp.

     9.   Miscellaneous.  If any provision of this Promissory Note shall be
          -------------
invalid or unenforceable for any reason, the same shall be ineffective, but the
remainder of this Promissory Note shall not be affected thereby and shall remain
in full force and effect.  Time is of the essence of each and every obligation
of Borrower hereunder.  Presentment and demand for payment, notice of dishonor,
protest and notice of protest are hereby waived by Borrower.  If the due date
for any payment under this Promissory Note falls on a Saturday, Sunday or legal
holiday, then such due date shall be extended to the next business day.  None of
the terms or provisions of this Promissory Note may be waived, altered, modified
or amended except by a writing signed by E-Stamp and Borrower.  The provisions
of this Promissory Note shall be

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governed by California law.  The covenants, terms and conditions hereof shall
bind the heirs, successors and assigns of Borrower and shall inure to the
benefit of the successors and assigns of E-Stamp.

     IN WITNESS WHEREOF, Borrower has executed this Promissory Note as of the
date first set forth above.

                                        BORROWER:

                                        /s/ Robert H. Ewald
                                        ----------------------------------------
                                        Robert H. Ewald

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                                                                   Exhibit 10.25

                            Stock Pledge Agreement

     This Stock Pledge Agreement ("Agreement") is made and entered into as of
this 22nd day of December, 1999 ("Effective Date") by and between Marcelo
Gumucio ("Director") and Carole Gumucio (collectively, "Pledgor") and E-STAMP
CORPORATION, a Delaware corporation ("E-Stamp").

                                   RECITALS
                                   --------

     A.   E-Stamp agreed to make a loan ("Loan") to Pledgor in the amount of
Borrower's personal income tax liability arising in 1999 from a stock award of
fifty thousand (50,000) shares of common stock of E-Stamp ("Shares") granted by
E-Stamp to Director on August 18, 1999.

     B.   Pledgor now desires to borrow the sum of One Hundred Fifty Thousand
Eight Hundred Eighty-five Dollars ($150,885) from E-Stamp to pay Pledgor's
income tax liability resulting from the issuance of the Shares, and to pledge
all right, title and interest in and seventeen thousand five hundred (17,500)
shares of common stock of E-Stamp ("Pledged Shares") upon the terms and
conditions set forth hereinbelow.

     NOW, THEREFORE, Pledgor hereby covenants and agrees as follows:

     1.   Pledge of Collateral.  Pledgor hereby pledges, assigns, grants and
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delivers to E-Stamp a security interest in all of Pledgor's right, title and
interest in and to the Pledged Shares and all cash and noncash proceeds and
substitutions thereof (collectively, the "Pledged Collateral") as security for
the prompt performance of Pledgor's obligations under the Loan.  The Pledged
Shares are evidenced by the stock certificates listed on Exhibit A attached
hereto.

     2.   Pledgor's Covenants.  Pledgor hereby represents, warrants and
          -------------------
covenants to E-Stamp as follows:

          (a) Pledgor is the owner of the Pledged Collateral.

          (b) The Pledged Collateral is free and clear of any security
interests, liens, encumbrances or other interests other than this Agreement.

          (c) Pledgor has full power and authority to create a first lien on the
Pledged Collateral in favor of E-Stamp and no disability or contractual
obligation exists which would prohibit Pledgor from pledging the Pledged
Collateral pursuant to this Agreement.

          (d) Pledgor shall not transfer, assign, create or permit to exist any
other claim to, lien or encumbrance upon, or security interest in any of the
Pledged Collateral, and shall not permit Pledgor's rights in the Pledged
Collateral to be reached by attachment, levy or other judicial process.

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          (e) At E-Stamp's request, Pledgor shall execute and acknowledge such
other documents and instruments which E-Stamp deems necessary or desirable to
evidence, continue or preserve E-Stamp's security interest in the Pledged
Collateral and/or to otherwise effect any of the terms of this Agreement.

     The foregoing representations, warranties and covenants shall survive the
termination of this Agreement.

     3.   Partial Release; Payment of Proceeds.
          ---------------- -------------------

          (a) Provided that Pledgor has not been in default hereunder or under
the Loan and the Loan is not otherwise due and payable, the security interest
created hereunder in the Pledged Collateral shall, from time to time, be
partially released on the applicable release dates pursuant to the schedule
attached as Exhibit A hereto, and E-Stamp shall promptly deliver to Pledgor the
applicable certificate for the Pledged Shares to which the security interest
hereunder is so released.

          (b)  All monies or other proceeds payable to Pledgor in connection
with the sale or transfer of any Pledged Shares shall be applied first to the
payment of principal, accrued interest and other charges then outstanding under
the Loan. Upon Pledgor's payment to E-Stamp of all principal, accrued interest
and other charges under the Loan and this Agreement, the security interest
created under this Agreement shall automatically terminate, and E-Stamp shall
promptly deliver to Pledgor any remaining Pledged Collateral then held by E-
Stamp.

          (c)  With respect to the disposition of any Pledged Shares, Pledgor
shall instruct Pledgor's stock broker ("Broker") to pay directly to E-Stamp from
Broker's account an amount equal to the lesser of (i) the sales price of the
Pledged Shares, less commissions, or (ii) the amount of principal, accrued
interest and other charges then outstanding under the Loan.  E-Stamp shall have
no obligation to deliver the Pledged Shares to Broker unless and until E-Stamp
receives written confirmation from Broker that the foregoing payment shall be
promptly made by Broker to E-Stamp.

          (d) E-Stamp shall retain possession of such shares until either (i)
all principal, accrued interest and other charges under the Loan have been paid
in full or (ii) Pledgor effects the sale of the Pledged Shares and applies the
applicable proceeds to any principal, accrued interest and other charges then
outstanding under the Loan as provided herein.  If Pledgor desires to sell any
such Pledged Shares, Pledgor shall instruct Broker to pay directly to E-Stamp
from Broker's account an amount equal to the lesser of (i) the sales price of
the Pledged Shares, less commissions, or (ii) the amount of principal, accrued
interest and other charges then outstanding under the Loan.  E-Stamp shall have
no obligation to deliver the Pledged Shares to Pledgor or Broker unless and
until E-Stamp receives written confirmation from Broker that the foregoing
payment shall be promptly made by Broker to E-Stamp.

          (e)  All instructions required to be submitted by Pledgor to Broker
shall be irrevocable and in writing, with a copy thereof delivered concurrently
to E-Stamp.  All proceeds paid for the Pledged Shares (less commissions) and
otherwise payable to E-Stamp hereunder shall be deposited directly into the
account of Broker for payment to E-Stamp.  E-Stamp's delivery of any Pledged
Shares to Broker shall be for the sole purpose of facilitating the sale of such
Pledged Shares, and E-Stamp's security interest therein shall continue until
Broker shall have paid to E-Stamp all applicable sums as required hereinabove.

     4.   Events of Default.  Each of the following shall constitute an event of
          -----------------
default ("Event of Default") hereunder:

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          (a) The failure by Pledgor to observe or perform any of the provisions
of this Agreement or to pay any amount due under the Loan and/or this Agreement.

          (b) The inaccuracy or breach of any warranty, representation or
statement made or furnished to E-Stamp by or on behalf of Pledgor.

          (c) The assignment for the benefit of creditors or the commencement of
any proceeding under any bankruptcy or insolvency law by or against Pledgor.

          (d) The seizure or attachment of, or a levy on all or any portion of
the Pledged Collateral.

     5.   E-Stamp's Remedies Upon Default.
          -------------------------------

          (a) Upon the occurrence of an Event of Default, E-Stamp shall have the
right to:

              (i)   Declare all of the obligations and liabilities of Pledgor
under the Loan immediately due and payable;

              (ii)  Repurchase all or part of the Pledged Shares from Pledgor
for a purchase price equal to the lesser of (i) the fair market value of such
Pledged Shares as of the date of the Event of Default, or (ii) the fair market
value of such shares as of the date of repurchase. The fair market value shall
be the closing sales price of the common stock of E-Stamp as reported in the
Wall Street Journal as of the applicable date set forth herein; and/or

              (iii) Exercise any and all rights of a secured party under the
Uniform Commercial Code of the State of California which E-Stamp, in its sole
judgment, deems necessary or appropriate, including, without limitation, the
right to sell or otherwise dispose of all or any part of the Pledged Collateral;

          (b) After the repurchase, sale or transfer of any of the Pledged
Collateral, E-Stamp may deduct all reasonable attorneys' fees, brokerage
commissions and other expenses incurred by E-Stamp in preserving, collecting,
selling, repurchasing and/or delivering the Pledged Collateral and for enforcing
its rights with respect to the Loan and this Agreement, and shall apply the
residue of the proceeds to, or hold as a reserve against, the Loan in such
manner as E-Stamp in its reasonable discretion shall determine, and shall
thereafter pay the balance, if any, to Pledgor.

     6    E-Stamp's Duties.  E-Stamp shall have no duty or liability for the
          ----------------
Pledged Collateral except for the exercise of reasonable care of the Pledged
Collateral while in the possession of E-Stamp.

     7.   General Provisions.
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          (a) Successors and Assigns.  This Agreement shall bind and inure to
              ----------------------
the benefit of the respective heirs, successors and permitted assigns of each of
the parties; provided, however, that neither this Agreement nor any rights
hereunder may be assigned by Pledgor without E-Stamp's prior written consent,
which consent may be granted or withheld in E-Stamp's sole discretion.

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          (b) Severability of Provisions.  Each provision of this Agreement
              --------------------------
shall be severable from every other provision of this Agreement for the purpose
of determining the legal enforceability of any specific provision.  In case one
or more of the provisions contained in this Agreement shall for any reason be
held invalid, illegal or unenforceable in any respect, the invalidity,
illegality or unenforceability of that provision shall not affect any other
provision of this Agreement.

          (c) Joint and Several Obligations.  If Pledgor consists of more than
              -----------------------------
one person, the obligations of Pledgor shall be the joint and several
obligations of all such persons.  When the context and construction so require,
all words used in the singular herein shall be deemed to have been used in the
plural and the masculine shall include the feminine and neuter and vice versa.

          (d) No Waiver.  No delay or omission by E-Stamp in exercising any
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right or remedy arising from any default of Pledgor shall be construed as a
waiver of such default or as an acquiescence therein, nor shall any single or
partial exercise thereof preclude any further exercise thereof.  E-Stamp may, at
its option, waive any of the conditions herein and any such waiver shall not be
deemed the waiver of E-Stamp's rights hereunder.  The waiver of any Event of
Default shall not be construed as any waiver of or acquiescence in or consent to
any preceding or subsequent Event of Default by Pledgor hereunder.

          (e) Collection Costs.  Pledgor shall promptly pay E-Stamp all
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reasonable attorneys' fees and all costs and other expenses paid or incurred by
E-Stamp in enforcing or exercising its rights or remedies created by, connected
with or provided in this Agreement, and payment thereof shall be secured by the
Pledged Collateral.

     IN WITNESS WHEREOF, this Pledge Agreement has been executed as of the
Effective Date.

                                        PLEDGOR:

                                        /s/ Marcelo Gumucio
                                        ------------------------------
                                        Marcelo Gumucio

                                        /s/ Carole Gumucio
                                        ------------------------------
                                        Carole Gumucio

                                        E-STAMP CORPORATION,
                                        a Delaware corporation

                                        By /s/ Ed Malysz
                                          -------------------------------------
                                        Its Vice President and General Counsel
                                           ------------------------------------

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                                   EXHIBIT A

                          LIST OF STOCK CERTIFICATES
                                      AND
                                 RELEASE DATES

     Certificate Number          Shares           Release Date
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                                 2,188           Effective Date
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                                 2,188               2/18/00
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                                 2,188               5/18/00
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                                 2,188               8/18/00
--------------------------------------------------------------------------------
                                 2,187              11/18/00
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                                 2,187               2/18/01
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                                 2,187               5/18/01
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                                 2,187               8/18/01
--------------------------------------------------------------------------------

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