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                                                                    Exhibit 10.5

                             MODIFICATION AGREEMENT

This Modification Agreement, dated as of June 26 2002, is entered into by and
between UMB Financial Corporation, a Missouri corporation headquartered at 1010
Grand Boulevard, Kansas City, Missouri 64106 ("Buyer"), and Miriam M. Allison,
an individual whose mailing address is 207 E. Buffalo Street, Suite 650,
Milwaukee, Wisconsin 53202 ("Allison").

Recitals

A.   Sarah Hammond, Rebekah Allison, Matthew Allison, and Peter Hammond (collec-
     tively the "Other Sellers"), Buyer and Allison entered into that certain
     Stock Purchase Agreement dated as of April 3, 2001 (the "Purchase
     Agreement"), under which Buyer acquired all of the capital stock of
     Sunstone Financial Group, Inc. a Wisconsin corporation ("Company").

B.   Pursuant to the Purchase Agreement, Buyer agreed to pay to Allison and the
     Other Sellers the "Earn-Out Payments" referred to in Section 1.2(c)of the
     Purchase Agreement, such Earn-Out Payments being calculated upon the "Gross
     Revenues" (as such term is defined in Section 1.2(c) of the Purchase
     Agreement) of Company during stated periods of time.

C.   Buyer now desires to employ Vincent Ciavardini ("Employee") to manage
     certain Company operations, with the intent of procuring significant new
     business from one or more Designated Funds or Designated Fund Servicers (as
     such terms are defined herein).

D.   Buyer has informed Allison that in order to induce Employee to accept
     employment with the Company and to undertake such efforts as may be needed
     in order to obtain business from Designated Funds and/or Designated Fund
     Servicers, Company will incur substantial expenses in the form of capital
     investments in software and other expenses and in making certain
     compensation and financial arrangements with Employee, and that such
     payments and expenses, together with the Earn-Out Payments that would
     otherwise be payable to Allison under the existing terms of the Purchase
     Agreement with respect to Gross Revenues associated with new business from
     Designated Funds and/or Designated Fund Servicers, would create such a high
     level of expense that such business would not be economically viable.

E.   Buyer has thus concluded that it is not an economically viable course of
     action for it to employ Employee and to seek to procure business from
     Designated Funds and/or Designated Fund Servicers unless Allison first
     agrees to modify Buyer's obligations under the Purchase Agreement so as to
     reduce the level of Earn-Out Payments that Allison is eligible to receive
     under the Purchase Agreement with respect to Gross Revenues associated with
     Designated Funds and/or Designated Fund Servicers, but without affecting
     Earn-Out Payments that the Other Sellers are entitled to receive under the
     existing terms of the Purchase Agreement.

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F.   Allison has indicated that she is willing to agree to such modification,
     provided that Buyer makes certain commitments as to other aspects of
     Company's operations.

G.   The parties thus desire to reduce their agreements to writing and modify
     and amend certain rights and obligations they have vis-a-vis each other
     under the Purchase Agreement.

NOW THEREFORE, in consideration of the premises and the mutual agreements of the
parties, the parties hereby agree as follows:

1.   Certain Definitions. When used in this Modification Agreement, the
     following terms shall have the meaning specified:

     "Absorbed Fund" shall mean a Currently Serviced Fund that later becomes a
     Designated Fund as a result of a merger, consolidation, assignment and
     assumption, or other corporate transaction, or which later becomes a
     Designated Fund solely by reason of appointing as its Investment Advisor an
     Investment Advisor that is an Affiliate of an entity listed on Exhibit A
     attached to this Agreement and who has no substantial influence over the
     selection of the Fund Servicer which will be retained to provide Fund
     Services to the Designated Fund from time to time.

     "Affiliate" of a party shall mean an entity that controls, is controlled
     by, or is under common control with, such party.

     "Control" shall mean the power to exercise a controlling influence over the
     management or policies of an entity (including (without limitation) with
     respect to a Fund or Fund Servicer, the selection or appointment of the
     entity(s) that are to provide Fund Services to such Fund or Fund
     Servicer), whether direct or indirect and whether by virtue of ownership of
     stock or other equity interests, voting power, contract rights or other
     means.

     "Currently Serviced Fund" means a Fund to which Fund Services are being
     provided or made available by Company or Buyer (or any of their respective
     Affiliates) or by a Currently Serviced Fund Servicer as of the relevant
     date of inquiry.

     "Currently Serviced Fund Servicer" shall mean any Fund Servicer that, as of
     the relevant time of inquiry, is receiving Fund Services from Buyer or the
     Company (or any of their Affiliates) and which in turn provides or makes
     those Fund Services available to one or more Funds.

     "Designated Fund" shall mean any of the following: (A) a Fund whose
     Investment Advisor or Distributor is, or is an Affiliate of, any of the
     entities (or any affiliate of any such entity) listed on Exhibit A attached
     hereto (each, an "Entity"); (B) a Fund that is a member of a Fund Complex
     listed on Exhibit A attached hereto or of which a Designated Fund also is a
     member; or (C) a Fund with respect to which any Entity or its Affiliate has
     the power or ability to select the provider of Fund Services to such Fund
     (or to a Fund Servicer who provides Fund Services to such Fund), or has the
     power or ability to control the outsourcing of Fund Services for such Fund.
     The fol-

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     lowing rules shall govern the status of whether a Fund constitutes a
     Designated Fund in the context of the specific circumstances addressed:

          .    If a Designated Fund should change its name at any time without
               otherwise affecting its continuity or structure, it nonetheless
               shall remain a Designated Fund.

          .    If a Designated Fund merges or otherwise consolidates with one or
               more other Funds that is/are not Designated Fund(s) or Currently
               Serviced Fund(s), then, following such merger or consolidation,
               the surviving or resulting Fund shall: (a) be considered a
               Designated Fund as a result of such merger or consolidation, if
               the total assets of the Designated Fund, immediately prior to the
               merger or consolidation, are greater than the total assets of all
               other Funds which are a party to the merger or consolidation,
               immediately prior to the merger or consolidation; and (b) not be
               considered a Designated Fund as a result of such merger or
               consolidation, if the total assets of the Designated Fund,
               immediately prior to the merger or consolidation, are less than
               the total assets of all other Funds that are a party to the
               merger or consolidation, immediately prior to the merger or
               consolidation.

     "Designated Fund Servicer" shall mean any Fund Servicer providing Fund
     Services to a Designated Fund, but only with respect to, and to the extent
     of, such Fund Services. The following rules shall govern the status of
     whether a Fund Servicer constitutes a Designated Fund Servicer in the
     context of the specific circumstances addressed:

          .  If a Designated Fund Servicer should change its name at any time
             without otherwise affecting its continuity or structure, it
             nonetheless shalt remain a Designated Fund Servicer;

          .  If a Designated Fund Servicer merges or otherwise consolidates with
             one or more other Fund Servicer(s) that is/are not Designated Fund
             Servicer(s) or a Currently Serviced Fund Servicer, then, following
             such merger or consolidation, the surviving or resulting Fund
             Servicer shall: (a) be considered a Designated Fund Servicer as a
             result of such merger or consolidation, if the total assets,
             immediately prior to the merger or consolidation, of the Designated
             Funds to which it provided Fund Services are greater than the total
             assets, immediately prior to the merger or consolidation, of all
             Funds (other than Designated Funds) to which the other Fund
             Servicer party (parties) to the merger or consolidation provided
             Fund Services; and (b) not be considered a Designated Fund Servicer
             as a result of such merger or consolidation, if the total assets,
             immediately prior to the merger or consolidation, of the Designated
             Funds to which it provided Fund Services are less than the total
             assets, immediately prior to the merger or consolidation, of all
             Funds (other than Designated Funds) to which the other Fund
             Servicer party(s) to the merger or consolidation provided Fund
             Services.

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          "Distributor" shall mean the entity that serves as principal
          underwriter or distributor for the shares of a Fund.

          "Fund" shall mean any mutual fund, whether organized as a stand-alone
          registered investment company or whether a series of a registered
          investment company authorized to designate and offer its shares or
          other units of beneficial ownership interest in multiple series.

          "Fund Complex" shall mean any two or more Funds that: (a) hold
          themselves out to investors as related companies for purposes of
          investment and investor services and/or that are marketed or promoted
          under a common name; or (b) have a common Investment Advisor or
          whose Investment Advisors are Affiliates of each other; or (c) have a
          common Distributor or whose Distributors are Affiliates of each other.

          "Fund Servicer" shall mean any investment advisor, distributor,
          underwriter, fund accountant, transfer agent or other entity providing
          Fund Services to a Fund or Fund Servicer, but only with respect to,
          and to the extent of, such Fund Services.

          "Fund Services" shall mean services as Distributor, Investment
          Advisor, call management, fulfillment and marketing services (even
          if not provided in a role as Distributor), fund accounting services,
          custody services, transfer agent services, fund administrative
          services, shareholder services, cash management services and the like
          commonly provided to Funds or Fund Servicers by the Company or Buyer
          or any of their respective Affiliates.

          "Investment Advisor" shall mean the primary investment advisor for a
          Fund, as opposed to a subadvisor.

          "Measuring Period" shall mean the period commencing on the first day
          of Employee's employment with Buyer or any Affiliate of Buyer and
          continuing for a period of six months following the date on which
          Employee no longer is employed with Buyer or any Affiliate of Buyer.

   2.     Modification to Earn-Out Calculation. For purposes of calculating
          Earn-Out Payments to be paid to Allison by Buyer under the Purchase
          Agreement, 60% of the Gross Revenues derived from Fund Services
          provided to Designated Funds or Designated Fund Servicers which first
          become customers of Company or Buyer (or their Affiliates) during the
          Measuring Period shall be excluded from the Gross Revenues upon which
          such Earn-Out Payments are computed during the five Earn-Out Periods
          identified in Exhibit D to the Purchase Agreement. Notwithstanding
          anything herein or in the Agreement to the contrary, to the extent
          that a Currently Serviced Fund hereafter becomes an Absorbed Fund
          (and thus, a Designated Fund), then the following special rule shall
          apply for the calculation of Earn-Out Payments payable to Allison with
          respect to Gross Revenues derived from Fund Services provided to such
          Absorbed Fund/Designated Fund after the date that it becomes an
          Absorbed Fund/Designated Fund (the "Absorption Date"):

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         .         First, promptly following the Absorption Date, there shall
                   be calculated a ratio (the "Absorption Ratio"). The numerator
                   of the Absorption Ratio shall be the actual Gross Revenues
                   derived from Fund Services provided to the Currently Serviced
                   Fund during the most recently completed calendar month prior
                   to the Absorption Date, adjusted to reflect the fee schedule
                   for Fund Services that will be applicable for Fund Services
                   provided to the Absorbed Fund/Designated Fund following the
                   Absorption Date, as though such fee schedule had been in
                   place and applicable to the Currently Serviced Fund during
                   such calendar month. The denominator of the Absorption Ratio
                   shall be a projection of monthly gross revenues to be derived
                   from Fund Services provided to the Absorbed Fund/Designated
                   Fund, such projection to be calculated based upon: (i) the
                   fee schedule for Fund Services in effect for the Absorbed
                   Fund/Designated Fund following the Absorption Date; (ii) the
                   total assets of the Absorbed Fund/Designated Fund as of the
                   Absorption Date; (iii) the total number of shareholder
                   accounts of the Absorbed Fund/Designated Fund as of the
                   Absorption Date; and (iv) the combined total number of
                   transactions and other account activity relevant under the
                   fee schedule during the most recently completed calendar
                   month prior to the Absorption Date for the Currently Serviced
                   Fund and any other Fund(s) involved in the Absorption
                   Transaction.

         .         Next, the Gross Revenues actually derived from Fund Services
                   provided to such Absorbed Fund/Designated Fund after its
                   Absorption Date shall be adjusted downward to an amount equal
                   to the sum of the following: (i) the product of such actual
                   Gross Revenues multiplied by the Absorption Ratio; plus (ii)
                   forty percent (40%) of the following: such actual Gross
                   Revenues minus the amount calculated in clause (i) of this
                   bullet point.

    By way of illustration of the foregoing, assume the following facts:

         .         Adjusted revenues derived from Fund Services provided to a
                   Currently Serviced Fund during the most recently completed
                   calendar month prior to its Absorption Date are $25,000;

         .         Revenues projected to be derived from the Absorbed Fund/
                   Designated Fund for the first month following its Absorption
                   Date are $100,000: and

         .         Actual revenues derived from the Absorbed Fund/Designated
                   Fund during the first year following the Absorption Date are
                   $1.5 million.

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         Then the Absorption Ratio is one-fourth ($25,000/$100,000), and the
         portion of the actual Gross Revenues that would be used to calculate
         the amount of the Earn-Out Payment owing to Allison with respect to the
         Absorbed Fund for the initial one-year period following the Absorption
         Date would be $825,000, calculated as follows:

                  $1,500,000 x 1/4                = $375,000
                 ($1,500,000 - $375,000) x 40%    =  450,000
                                                    --------
                       Total                      = $825,080
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 3.      UMB Commitment. UMB hereby agrees that if: (a) Company hereafter enters
         into a binding contract or letter of intent or other commitment deemed
         satisfactory by UMB for the provision of Fund Services to one or two
         Fund Complexes to whom Company does not presently provide Fund
         Services, or enters into a binding contract or letter of intent or
         other commitment deemed satisfactory by UMB for the provision of
         transfer agency services to one or two Fund Complexes to whom Company
         currently provides other Fund Services but not transfer agency
         services, and (b) the provision of such new or additional Fund Services
         under such binding contract or letter of intent is reasonably projected
         to generate at least two million dollars ($2,000,000) in Gross Revenues
         to Company (excluding client reimbursements) during the twelve-month
         period following conversion, then Buyer promptly (in connection with
         the conversion(s) or other startup of the provision of Fund Services to
         such Fund Complex(es)) shall purchase or license or otherwise acquire
         the right to use or the use of, a new stock transfer agency software
         system and other resources appropriate in order for Company to provide
         competitive transfer agency services and products to such Fund
         Complex(es) as well as to Company's other clients, it being understood
         that such system may be purchased, leased, outsourced, accessed by
         remote usage, or otherwise obtained; provided however that no such
         action shall be required if Buyer determines, and Allison agrees (such
         agreement not to be unreasonably withheld), that the acquisition of
         such system and resources would constitute an unreasonable economic
         investment on the part of Company or Buyer.

 4.      Fees. Buyer agrees to pay the sum of $20,000 to Allison to reimburse
         her for legal and consultant expenses reasonably incurred by her in
         negotiating and preparing this Modification Agreement.

 5.      Effect on Purchase Agreement. This Modification Agreement is intended
         to amend the Purchase Agreement as necessary to reflect the calculation
         of Earn-Out Payments payable by Buyer to Allison as provided for
         herein, and to incorporate the Buyer's covenants set forth in Paragraph
         3 hereof. Except as so explicitly modified, the terms and conditions of
         the Purchase Agreement shall continue in full force and effect in
         accordance therewith, unmodified by this Modification Agreement.
         Without limiting the generality of the foregoing, nothing in this
         Modification Agreement is intended to affect in any respect any right
         or obligation of any of the Other Sellers. As a matter of confirmation
         and clarification and without limiting the generality of the preceding
         sentence, the formula and basis for calculation of Earn-Out Payments
         payable by the Buyer to the Other Sellers under the terms of the
         Purchase Agreement remain in full force and effect, unaffected by the
         provisions of this Modification Agreement.

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6.   Capitalized Terms. Except as explicitly defined otherwise herein, all
     capitalized terms shall have the meanings ascribed to them in the Purchase
     Agreement.

IN WITNESS WHEREOF, this Modification Agreement has been duly executed and
delivered as of the date first above written.

UMB Financial Corporation "BUYER"

By: /s/ Daniel C. Stevens                 /s/ Miriam M. Allison
   ----------------------------------    -------------------------------------
                                         Miriam M. Allison "ALLISON"
Name:   Daniel C. Stevens
     --------------------------------
Title:  EVP + CFO
      -------------------------------

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                                    EXHIBIT A

                                     OMITTED