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                                                                   EXHIBIT 10.18

                               EXCHANGE AGREEMENT

         THIS EXCHANGE AGREEMENT, dated as of September 23, 2003, is by and
among Oak Street Financial Services, Inc., a Maryland corporation (the
"Company"), Oak Street Operations LLC, a Delaware limited liability company
("OSO") and unitholders ("Unitholders") of Oak Street Mortgage LLC, a Delaware
limited liability company ("OSM").

                                    RECITALS

         A.       OSO proposes to offer one of its units in exchange for each
unit of OSM held by the Unitholders. Voting units of OSM will be exchanged for
voting units of OSO, and non-voting units of OSM will be exchanged for
non-voting units of OSO. Units of OSM are hereinafter referred to as "OSM
Units." Units of OSO are hereinafter referred to as "OSO Units."

         B.       Immediately following the exchange of units in Paragraph A,
the Company proposes to offer 1,000 shares of its common stock, $.01 par value
per share ("Common Stock"), in exchange for each OSO Unit held by the
Unitholders, except for the 113,999.95 non-voting OSO Units owned by Sotseks
Corp. ("Sotseks") which shall be the subject of a stock purchase option
referenced in Article II, Section 7. Voting shares of Common Stock will be
exchanged for voting OSO Units on a 1,000 share to one unit basis. Non-voting
shares of Common Stock will be exchanged for non-voting OSO Units on a 1,000
share to one unit basis.

         C.       Each Unitholder owns the OSM Units listed opposite his, her,
or its name on Exhibit A hereto.

         D.       OSO desires to acquire the OSM Units from each Unitholder, and
each Unitholder is willing to transfer to OSO, the OSM Units set forth beside
such Unitholder's name on Exhibit A hereto, in exchange, in each case, for the
OSO Units set forth opposite the name of the Unitholder on Exhibit A.

         E.       The Company desires to acquire the OSO Units from each
Unitholder except Sotseks, and each Unitholder is willing to transfer to the
Company, the OSO Units set forth beside such Unitholder's name on Exhibit A
hereto, in exchange, in each case, for the shares of Common Stock of the Company
set forth opposite the name of such Unitholder on Exhibit A (the "Shares").

         F.       The parties to this Agreement want to reduce to writing their
agreement with respect to the foregoing.

         THEREFORE, in consideration of the mutual covenants contained in this
Agreement and the acts to be performed under this Agreement, the parties hereby
agree to the following:

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                ARTICLE I - EXCHANGE OF OSM UNITS FOR OSO UNITS
                           AND OF OSO UNITS FOR SHARES

         1.       TRANSFER OF THE OSM UNITS. Subject to the terms and conditions
of this Agreement, each Unitholder agrees to transfer to OSO on the Closing Date
(as defined in Section 3) all of the Unitholder's right, title and interest in
and to the OSM Units set forth beside such Unitholder's name on Exhibit A
attached to this Agreement.

         2.       ISSUANCE OF OSO UNITS. As consideration for the OSM Units, on
the Closing Date OSO shall issue to each Unitholder the OSO Units set forth
opposite such Unitholder's name on Exhibit A.

         3.       TRANSFER OF OSO UNITS. Subject to the terms and upon the
conditions of this Agreement, each holder of OSO Units except Sotseks agrees to
transfer to the Company on the Closing Date all of such holder's right, title
and interest in and to the OSO Units set forth opposite his, her or its name on
Exhibit A.

         4.       ISSUANCE OF SHARES. As consideration for the OSO Units
transferred to it on the Closing Date, the Company shall issue to each holder of
OSO Units transferring such OSO Units to the Company, the number and class of
Shares set forth opposite such person's name on Exhibit A.

         5.       CLOSING. The closing (the "Closing") of the transfer of the
OSM Units and the OSO Units and the acquisition of the OSO Units and the Shares
described in this Agreement shall be held as soon as practicable after OSO and
the Company receive signed signature pages and the OSM Unit Assignment Form from
each Unitholder and the OSO Unit Assignment Form and a signed Form 2553 from
each Unitholder except Sotseks (the "Closing Date"), at the offices of the
Company, 11595 N. Meridian Street, Suite 400, Carmel, Indiana 46032, or at such
other time and place as is mutually agreed to by the parties to this Agreement.

         6.       SUBCHAPTER S PROVISIONS.

         (a)      The Company intends to elect to be an S Corporation for and
                  after its date of organization.

         (b)      Each shareholder of the Company, agrees to sign a Form 2553
                  including any attachments thereto to make such an election.
                  The Company will provide each such Unitholder with a copy of
                  the Form 2553 to be signed by such Unitholder.

         7.       REPRESENTATIONS AND WARRANTIES OF THE UNITHOLDERS. Each
Unitholder hereby represents and warrants to OSO and to the Company with respect
to the OSM Units and OSO Units set forth beside such Unitholder's name on
Exhibit A, as follows:

         (a)      The Unitholder is the record and beneficial owner of the OSM
                  Units.

         (b)      The transfer of the OSM Units by the Unitholder to OSO
                  hereunder will vest in OSO good and valid right, title and
                  interest in and to the OSM Units, free and clear of all
                  claims, liens, pledges, charges, security interests and
                  encumbrances of

                                      -2-

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                  any nature. The transfer of the OSO Units to the Company
                  hereunder will vest in the Company good and valid right, title
                  and interest in and to the OSO Units, free and clear of all
                  claims, liens, pledges, charges, security interests and
                  encumbrances of any nature.

         (c)      The Unitholder has the full right, power and authority to
                  execute, deliver and perform this Agreement and to transfer
                  the OSM Units and, in the case of all Unitholders but Sotseks,
                  the OSO Units in accordance herewith.

         (d)      This Agreement constitutes the legal, valid and binding
                  obligation of the Unitholder, enforceable against such
                  Unitholder in accordance with its terms, except as such
                  enforcement may be limited by bankruptcy, insolvency, or other
                  laws or equitable principles affecting the enforcement of
                  creditors' rights generally.

         (e)      The Unitholder has the financial ability to bear the economic
                  risk of an investment in the OSO Units and in the Shares, as
                  applicable, has adequate means of providing for his, her or
                  its current needs and personal contingencies, has no need for
                  liquidity in such investment and could afford the complete
                  loss of such investment. The Unitholder's overall commitment
                  to investments that involve a high degree of risk or that are
                  not readily marketable is not disproportionate to the
                  Unitholder's net worth, and the Unitholder's investment in OSO
                  or in the Company will not cause such overall commitment to
                  become excessive.

         (f)      The Unitholder has such knowledge, skill and experience in
                  business, financial and investment matters that the Unitholder
                  is capable of evaluating independently the merits and risks of
                  an investment in OSO Units or in the Shares. To the extent the
                  Unitholder has determined it to be necessary, the Unitholder
                  has retained, at the Unitholder's own expense, and relied
                  upon, appropriate professional advice regarding the
                  investment, tax and legal merits and consequences of this
                  Agreement and ownership of the OSO Units or the Shares.

         (g)      All representations, warranties and covenants contained in
                  this Agreement shall survive the Closing Date and the death or
                  disability of the Unitholder if an individual, and shall be
                  binding on such Unitholder's successors and assigns.

         (h)      The Unitholder hereby covenants and agrees to notify the
                  Company upon the occurrence of any event prior to the Closing
                  Date which would cause any representation or warranty of the
                  Unitholder contained in this Agreement to be false or
                  incorrect.

         8.       REPRESENTATION AND WARRANTIES OF OSO. OSO hereby represents
and warrants to the Unitholders as follows:

         (a)      OSO is duly formed, validly existing and in good standing
                  under the laws of the State of Delaware, with full power and
                  authority to conduct its business and to execute and deliver
                  this Agreement and to perform its obligations hereunder.

                                      -3-
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         (b)      OSO has duly authorized the sale and issuance of the OSO Units
                  upon the terms set forth herein by all requisite corporate
                  action, and this Agreement has been duly authorized, executed
                  and delivered by it.

         (c)      this Agreement constitutes the legal, valid and binding
                  obligation of OSO, enforceable against OSO in accordance with
                  its terms, except as such enforcement may be limited by
                  bankruptcy, insolvency or other laws or equitable principles
                  affecting the enforcement of creditors' rights generally.

         9.       REPRESENTATIONS AND WARRANTIES OF THE COMPANY. The Company
hereby represents and warrants to the Unitholders as follows:

         (a)      The Company is duly formed, validly existing and in good
                  standing under the laws of the State of Maryland, with full
                  power and authority to conduct its business and to execute and
                  deliver this Agreement and to perform its obligations
                  hereunder.

         (b)      The Company has duly authorized the sale and issuance of the
                  Shares upon the terms set forth herein by all requisite
                  corporate action, and this Agreement has been duly authorized,
                  executed and delivered by it.

         (c)      This Agreement constitutes the legal, valid and binding
                  obligation of the Company, enforceable against the Company in
                  accordance with its terms, except as such enforcement may be
                  limited by bankruptcy, insolvency or other laws or equitable
                  principles affecting the enforcement of creditors' rights
                  generally.

         10.      COVENANTS. Each Unitholder agrees to the following:

         (a)      The Unitholder understands and agrees that, unless the
                  Unitholder notifies the Company in writing to the contrary on
                  or before the Closing Date, all of the Unitholder's
                  representations and warranties contained in this Agreement
                  will be deemed to have been reaffirmed and confirmed as of the
                  Closing Date.

         (b)      The Unitholder understands that no federal or state agency has
                  made any findings or determination as to the fairness of an
                  investment in, or any recommendation or endorsement of, the
                  OSO Units or the Shares.

         (c)      The Unitholder acknowledges that OSO and the Company have the
                  right in their sole and absolute discretion to abandon this
                  offer at any time prior to the Closing Date and to return to
                  the Unitholder his, her or its Units.

         (d)      Each of the Unitholders acknowledges receipt of the letter
                  dated September ___, 2003, from Steven Alonso describing the
                  transactions contemplated by this Agreement, and the
                  enclosures referred to in that letter (the "Documentation").
                  Each Unitholder represents that the decision he, she or it has
                  made regarding whether or not to assign OSM Units to OSO in
                  exchange for OSO Units, and OSO Units to the Company in
                  exchange for Shares pursuant to this Agreement ("Exchange
                  Decision") has been made by such Unitholder independently
                  after

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                  considering the Documentation, the tax consequences of that
                  decision, and other relevant information, and after consulting
                  any professional advisors deemed appropriate by such
                  Unitholder. Each Unitholder covenants that he, she or it will
                  assert no claim against OSM, OSO, the Company, their
                  subsidiaries, or their officers, directors or agents based on
                  such Unitholder's Exchange Decision or the disclosures made to
                  such Unitholder in connection with that Exchange Decision.
                  Each Unitholder hereby indemnifies and holds harmless OSM, OSO
                  and the Company, their subsidiaries, and their officers,
                  directors or agents from and against any loss or liability
                  occasioned by any such claim of such Unitholder or such
                  Unitholder's representatives.

         11.      INFORMATION CONCERNING OSO AND THE COMPANY.

         (a)      The Unitholder has had the opportunity to obtain information
                  or documents from, and to ask questions of, representatives of
                  OSO and the Company in connection with the offering of the OSO
                  Units and the Shares and any aspect of the business of OSO and
                  the Company, to the extent necessary to evaluate the merits
                  and risks (both economic and legal) related to the
                  Unitholder's investment in OSO and in the Company, and has
                  received answers therefrom that the Unitholder considers to be
                  responsive to such questions. Prior to making an investment in
                  OSO and in the Company, the Unitholder has had the opportunity
                  to verify the accuracy of any information that has been
                  provided.

         (b)      The Unitholder understands that no public market is available
                  for the sale of the OSO Units or the Shares at this time.

         12.      RESTRICTIONS ON TRANSFER OR SALE OF OSO UNITS AND SHARES UNDER
SECURITIES LAWS.

         (a)      The Unitholder is acquiring the OSO Units and, thereafter as
                  to each Unitholder except Sotseks, the Shares solely for the
                  Unitholder's own beneficial account, for investment purposes,
                  and not with a view to, or for resale in connection with, any
                  distribution of the OSO Units or the Shares (other than in
                  accordance with applicable federal or state law). The
                  Unitholder understands that neither the OSO Units nor the
                  Shares have been registered under the Securities Act of 1933
                  (the "Securities Act") or any state securities laws by reason
                  of specific exemptions under the provisions thereof which
                  depend in part upon the investment intent of the Unitholder
                  and of the other representations, warranties and covenants
                  made by the Unitholder in this Agreement. The Unitholder
                  understands that OSO and the Company are relying upon the
                  representations, warranties and covenants of the Unitholder
                  contained in this Agreement for the purpose of determining
                  whether this transaction meets the requirements for such
                  exemptions.

         (b)      The Unitholder understands that the OSO Units and the Shares
                  are "restricted securities" as that term is defined in Rule
                  144 promulgated under the Securities Act by the Securities and
                  Exchange Commission (the "Commission") and that the Securities
                  Act and Rule 144 and other rules promulgated by the Commission

                                      -5-
<PAGE>

                  provide in substance, if a public market for such securities
                  develops later, that the Unitholder may dispose of the OSO
                  Units and the Shares only pursuant to an effective
                  registration statement under the Securities Act or an
                  exemption therefrom, and the Unitholder understands that the
                  Company has no obligation or intention to register any of the
                  OSO Units or the Shares, or to take action so as to permit
                  sales pursuant to the Securities Act (including Rule 144).
                  Accordingly, the Unitholder understands that, under the
                  Commission's rules, the Unitholder may dispose of the OSO
                  Units and the Shares principally only in "private placements"
                  which are exempt from registration under the Securities Act,
                  in which event the transferee will acquire "restricted
                  securities" subject to the same limitations as in the hands of
                  the Unitholder.

         (c)      With the exception of the transfer of OSO Units to the Company
                  as contemplated by this Agreement, no Unitholder may offer,
                  sell or transfer OSO Units or Shares acquired by him, her or
                  it under this Agreement unless, at the expense of the
                  transferring Unitholder, the Company, in the case of a
                  transfer of Shares, or OSO, in the case of a transfer of OSO
                  Units, has received an opinion of counsel for the Company or
                  OSO or counsel acceptable to the Company or OSO, as the case
                  may be, to the effect that such transfer is exempt from
                  registration requirements under the Securities Act and state
                  securities laws. OSO's Management Committee as to the OSO
                  Units and the Company's Board of Directors, as to the Shares,
                  may, in its sole discretion, waive the requirement for a legal
                  opinion, but any such waiver will not constitute a waiver of
                  any such requirement for any subsequent transfer of such OSO
                  Units or Shares or any interest therein.

         (d)      With the exception of the transfer of OSO Units to the
                  Company, as contemplated by this Agreement, the Unitholder
                  acknowledges and agrees that the Unitholder will not sell,
                  assign, pledge, give, transfer or otherwise dispose of the OSO
                  Units or the Shares or any interest therein, or make any offer
                  or attempt to do any of the foregoing, except pursuant to a
                  registration of the OSO Units or the Shares, as applicable,
                  under the Securities Act and all applicable state securities
                  laws or in a transaction which is exempt from the registration
                  provisions of the Securities Act and all applicable state
                  securities laws.

         (e)      The Unitholder has not offered or sold any portion of the OSO
                  Units or the Shares and has no present intention of dividing
                  the OSO Units or the Shares with others or of reselling or
                  otherwise disposing of any portion of the OSO Units or the
                  Shares either currently or after the passage of a fixed or
                  determinable period of time or upon the occurrence or
                  nonoccurrence of any predetermined event or circumstance.

         13.      CONDITIONS PRECEDENT TO THE UNITHOLDERS' OBLIGATIONS. All
obligations of the Unitholders under this Agreement are subject to the
fulfillment, prior to or on the Closing Date, of each of the following
conditions:

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<PAGE>

         (a)      OSO's representations and warranties contained in this
                  Agreement shall be true at the time of Closing as though such
                  representations and warranties were made at such time;

         (b)      OSO shall have delivered to Sotseks a certificate representing
                  the non-voting OSO Units to which such Unitholder is entitled
                  under this Agreement;

         (c)      The Company's representations and warranties contained in this
                  Agreement shall be true at the time of Closing as though such
                  representations and warranties were made at such time; and

         (d)      The Company shall have delivered to each Unitholder except
                  Sotseks the stock certificates representing the number and
                  class of Shares to which such Unitholder is entitled under
                  this Agreement.

         14.      CONDITIONS PRECEDENT TO OSO'S OBLIGATIONS. All obligations of
OSO under this Agreement are subject to the fulfillment, prior to or on the
Closing Date, of each of the following conditions:

         (a)      The Unitholders' representations and warranties contained in
                  this Agreement shall be true at the time of Closing as though
                  such representations and warranties were made at such time;
                  and

         (b)      Each Unitholder shall have delivered to OSO on or before the
                  Closing an OSM Unit Assignment Form which assigns the OSM
                  Units to OSO.

         15.      CONDITIONS PRECEDENT TO THE COMPANY'S OBLIGATIONS. All
obligations of the Company under this Agreement are subject to the fulfillment,
prior to or on the Closing Date, of each of the following conditions:

         (a)      The Unitholders' representations and warranties contained in
                  this Agreement shall be true at the time of Closing as though
                  such representations and warranties were made at such time;

         (b)      Each Unitholder except Sotseks shall have delivered to the
                  Company on or before the Closing an OSO Unit Assignment Form
                  which assigns his, her or its OSO Units to the Company, a
                  signed signature page of this Agreement and an executed Form
                  2553 for such Unitholder; and

         (c)      OSO shall have delivered to the Company a certificate
                  representing the non-voting and voting units to which the
                  Company is entitled under this Agreement.

         16.      EFFECT OF CONDITIONS PRECEDENT. In the event the conditions
precedent to consummation of this Agreement are satisfied or waived by the party
they are to benefit on or before September 30, 2003, then the Unitholders, OSO,
and the Company shall proceed with the consummation of this Agreement;
otherwise, the obligations of the Unitholders, the Company, and OSO hereunder
shall be terminated.

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         17.      COVENANT OF FURTHER ASSURANCES. The Unitholders agree, upon
reasonable request, to deliver such additional documents to OSO or to the
Company or take such additional actions as may be necessary or appropriate to
vest in OSO ownership of the OSM Units and in the Company ownership of the OSO
Units held by unitholders other than Sotseks.

         18.      OSM OPERATING AGREEMENT. With regard to the exchange of OSM
Units for OSO Units pursuant to this Agreement by any Unitholder of OSM, the
undersigned Unitholder hereby waives any compliance with any and all covenants,
agreements, or requirements set forth in the Limited Liability Company Operating
Agreement of OSM (the "OSM Operating Agreement") or the Redemption Agreements by
and between OSM and certain Unitholders governing or otherwise restricting the
sale, transfer, and assignment of the OSM Units, including, without limitation,
any rights of first refusal or purchase that such Unitholder may have under
Article VII of the OSM Operating Agreement and Section 5 of the Redemption
Agreement. With regard to the exchange of OSM Units for OSO Units pursuant to
this Agreement by any Unitholder of OSM, OSM hereby unanimously waives any
compliance with (i) any and all covenants, agreements, or requirements set forth
in the OSM Operating Agreement governing or otherwise restricting the sale,
transfer, and assignment of the OSM Units, including, without limitation, the
provisions of Sections 7.2 and 7.3 of the OSM Operating Agreement, and (ii) any
and all covenants, agreements, or requirements set forth in the Redemption
Agreements by and between OSM and certain of its Unitholders governing or
otherwise restricting the sale, transfer, and assignment of their OSM Units,
including, without limitation, the provisions of Section 2, 3, 4 and 5 of the
Redemption Agreements. At the Closing, since OSO shall have acquired all OSM
Units, the Unitholders, in their capacity as Unitholders, shall no longer be
subject to the OSM Operating Agreement or the Redemption Agreements.

         19.      OSO OPERATING AGREEMENT. OSO and Sotseks agree as soon as
practicable after the Closing Date to enter into a Limited Liability Operating
Company Agreement of OSO in the form attached hereto as Exhibit B. Sotseks and
OSO agree not to transfer any OSO Units they receive pursuant to this Agreement
until the OSO Operating Agreement attached hereto as Exhibit B is executed, at
which point they will be subject to the transfer restrictions contained therein.

                        ARTICLE II - ADDITIONAL TRANSFER
                      RESTRICTIONS APPLICABLE TO THE SHARES

         1.       GENERAL RESTRICTIONS. Following the Closing, the Unitholders
acquiring Shares hereunder (the "Shareholders") shall have no right to sell,
assign or in any manner transfer all or any part of the Shares and the
Shareholders hereby agree that the Shareholders will not sell, assign or in any
manner transfer all or any part of the Shares, except as otherwise provided in
this Agreement, without the prior written consent of the Board of Directors of
the Company. The Board of Directors of the Company may require, as a condition
of such a sale, assignment or transfer of Shares, that the transferee execute an
agreement substantially identical in form to this Agreement (other than Article
I) (which may be accomplished by a certificate of acceptance and adoption of
this Agreement (other than Article I), that provides that all of the
transferee's Shares shall be subject to the restrictions on transfer set forth
in this Agreement (other than Article I).

                                      -8-
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         2.       RESTRICTIONS APPLICABLE TO SHAREHOLDERS OTHER THAN EMPLOYEE
SHAREHOLDERS. Except as specifically permitted in this Section 2, no holder of
Shares following the Closing Date who is not an Employee Shareholder, as defined
in Section 3 hereof, subject to the transfer restrictions in Section 3 hereof (a
"Non-Employee Shareholder") may sell, assign or in any manner transfer all or
any part of his, her or its Shares in the Company, without the unanimous written
consent of the Company's Board of Directors.

         (a)      Permitted Transfers. Notwithstanding anything to the contrary
                  in this Section 2 and except as provided in this Section 2,
                  any Non-employee Shareholder (including without limitation
                  such Non-employee Shareholder's legal guardian, executor or
                  administrator in the case of an individual Non-employee
                  Shareholder) desiring to sell, transfer, exchange or encumber
                  all or part of such Non-employee Shareholder's Shares,
                  including transfers by gift or by reason of death, may do so
                  only if such Non-employee Shareholder has complied with the
                  provisions of this Section 2 unless such provisions have been
                  waived in writing by the unanimous consent of the Company's
                  Board of Directors. Upon the transfer by a Non-employee
                  Shareholder of his, her, or its Shares in accordance with this
                  Section 2, said Non-employee Shareholder shall promptly
                  surrender to the Company any and all certificates evidencing
                  the transferred Shares, and the Company shall thereafter issue
                  to the new Shareholder a certificate evidencing the number of
                  Shares so acquired.

         (b)      Transfers to Family or Affiliates. Any Non-employee
                  Shareholder may, with the unanimous consent of the Board of
                  Directors of the Company, which consent shall not be
                  unreasonably withheld, transfer the Shares held by such
                  Non-employee Shareholder to persons related by blood to such
                  Non-employee Shareholder or to an entity in which a majority
                  of the equity interests or beneficial interests is held by
                  persons related by blood to such Non-employee Shareholder;
                  provided however that John F. Havens (or at his death, his
                  personal representative) may transfer his voting Shares to
                  Ellen H. Hardymon without seeking such consent and George A.
                  Skestos (or at his death, his personal representative) may
                  transfer his voting Shares to George Anthony Skestos without
                  seeking such consent. Such transfer may be made by the
                  Non-employee Shareholder or, in the event of the Non-employee
                  Shareholder's death or disability, by his or her personal
                  representative. A condition of such transfer shall be that
                  such prospective transferee shall agree to be bound by the
                  provisions in this Agreement (other than Article I).

         (c)      Response to Third Party Offer. The Havens Group shall mean
                  John F. Havens, trusts for the benefit of his children, his
                  children, and any transferee from any of such persons pursuant
                  to the provisions of this Section 2. The Skestos Group shall
                  mean George A. Skestos, Sotseks and any transferee from any of
                  such persons pursuant to the provisions of this Section 2. The
                  Alonso group shall mean Steven Alonso and any transferee from
                  him pursuant to the provisions of this Section 2. Such Groups
                  shall be bound by the majority vote of the Group of which they
                  are a part. If either the Havens Group, the Skestos Group or
                  the Alonso Group receives a written offer, by its terms
                  irrevocable for at least 30

                                      -9-
<PAGE>

                  days, to purchase all of the Shares and outstanding options of
                  such Group and such Group wishes to accept such offer, a
                  representative of such Group shall advise the members of the
                  other Groups of the terms of such offer within 10 days
                  following receipt thereof. The other Groups shall have the
                  right, for a period of 15 days following such receipt, to give
                  notice in writing to such Group that the other Groups elect to
                  purchase all of the Shares and outstanding options of such
                  Group at the price and on the terms proposed by the third
                  party purchaser, supported by credible financial assurances
                  that the other Groups are able to do so. Alternatively, the
                  other Groups may in a writing delivered within the same time
                  period elect to require that all of their Shares and
                  outstanding options be purchased at the same price and on the
                  same terms by the proposed third party purchaser. If the
                  proposed third party purchaser is unwilling to purchase all of
                  such offered Shares and outstanding options, then any Group
                  may reject such offer in its entirety or the Groups may agree
                  to sell, on a pro rata allocation, such number of Shares and
                  outstanding options as the proposed third party purchaser is
                  willing to buy.

         (d)      Transfer in the Event of the Death or Disability of Steven
                  Alonso. In the event of the death or disability of Steven
                  Alonso, the Company shall purchase all of the Shares of the
                  Alonso Group at the value established in accordance with the
                  valuation procedure described in subsection (g); provided,
                  however, that Mr. Alonso's personal representative, in the
                  event of his death or disability, may by written notice to the
                  Company elect within 90 days following such event to defer
                  establishment of the value of the Shares of the Alonso Group
                  for a period of 36 months following such event. Any purchase
                  by the Company shall be on a time schedule which accords with
                  available liquid assets of the Company and covenants in the
                  Company's financing agreements.

         (e)      Transfer in the Event of Bankruptcy or Divorce of a
                  Non-employee Shareholder. In the event of the bankruptcy of a
                  Non-employee Shareholder or in the event of a transfer of
                  Shares incident to a divorce, the Company shall purchase all
                  of the Shares of such Non-employee Shareholder at the value
                  established in accordance with subsection (g). Any purchase
                  shall be on a time schedule which accords with the available
                  liquid assets of the Company and complies with covenants in
                  its financing agreements.

         (f)      Other Disposition of Shares. If either the Havens Group, the
                  Skestos Group or the Alonso Group wishes to offer for sale all
                  of its Shares and outstanding options but has not received an
                  offer from a third party or if either group wishes to
                  liquidate the Company in order to terminate its interests in
                  the Company, the value of such interest shall be established
                  in accordance with the valuation procedure described in
                  subsection (g). The Groups which did not take the initial
                  action leading to such valuation (the "non-offering groups")
                  may elect to tender such Shares and outstanding options for
                  sale as part of a uniform sales effort or to purchase such
                  Shares and outstanding options at the value determined
                  pursuant to subsection (g). In the event that the non-offering
                  groups do not take action as described above, the Company may
                  elect to purchase the interest of the offering group at the
                  value

                                      -10-
<PAGE>

                  determined pursuant to subsection (g). Notice of such group's
                  election and the Company's election shall be given in writing
                  to the offering group within 15 days following delivery to it
                  of such valuation. In the event that the Alonso Group wishes
                  to offer for sale its Shares, the non-offering group does not
                  elect to purchase such Shares, and the Company is not willing
                  or financially able to purchase such Shares except in
                  accordance with a time schedule which is not acceptable to the
                  Alonso Group, the Company shall be liquidated.

         (g)      Valuation Procedures. In all events where the value of Shares
                  held by a given group is to be determined by independent
                  experts, the offering group shall select a person and the
                  non-offering groups shall jointly select a person, each said
                  person being qualified by experience to value businesses and
                  these two persons shall undertake to mutually agree upon the
                  value of such Shares. In the event that such persons are not
                  able to reach mutual agreement as to such value, they shall
                  select a third person qualified by experience to value
                  businesses to provide such valuation and that person's
                  valuation shall be conclusive.

         3.       RESTRICTIONS APPLICABLE TO EMPLOYEE SHAREHOLDERS. The
restrictions in this Section 3 shall apply to those holders of Units who are
currently employees of OSM, other than Steven Alonso (the "Employee
Shareholders"). They are designated as Employee Shareholders on the signature
pages to this Agreement.

         (a)      Upon the termination of an Employee Shareholder's employment
                  for any reason, the following actions shall take place:

                  (i)      The Employee Shareholder shall assign and transfer to
                           the Company all right, title and interest in the
                           Shares he or she owns, free and clear of all liens,
                           encumbrances and other claims. Within 10 days of such
                           termination of employment, the Employee Shareholder
                           shall deliver to the Company any and all certificates
                           representing the Shares for redemption and repurchase
                           by the Company.

                  (ii)     Upon delivery of the Share certificates, the Company
                           shall redeem and repurchase such Shares at the
                           Redemption Price. The Redemption Price per Share
                           shall be an amount equal to the greater of (1) the
                           Per Share Earnings multiplied by 3 or (2) the book
                           value of a Share on the date of repurchase by the
                           Company determined in accordance with generally
                           accepted accounting principles. "Per Share Earnings"
                           means the Company's Profit for the 12 consecutive
                           calendar months preceding the month in which a
                           termination of employment of the Employer Shareholder
                           shall occur or the month in which a Transfer Notice
                           is received by the Company, divided by the total
                           number of Shares of the Company which are outstanding
                           on the date of such redemption and repurchase.
                           "Profit" shall mean the sum of the Company's total
                           items of income set forth in Section 1367(a)(1)(A)
                           through (C) of the Code for the period in question
                           reduced by the sum of the Company's total items of
                           loss and deduction set forth in Section 1367(a)(2)(B)
                           through (E) of the Code for the period in question.

                                      -11-
<PAGE>

                  (iii)    The Company shall pay the Redemption Price to the
                           Employee Shareholder in cash or other immediately
                           available funds no later than 10 days after the
                           Employee Shareholder's delivery to the Company of the
                           certificates representing the Shares.

         (b)      In the event that an Employee Shareholder's employment is
                  terminated as a result of the Employee Shareholder's death,
                  all of the obligations of the Employee Shareholder shall be
                  performed by the Employee Shareholder's personal
                  representative and the Redemption Price paid by the Company
                  shall be paid to such personal representative. For this
                  purpose, the term "personal representative" shall mean an
                  administrator, executor, trustee, or other personal
                  representative who is vested with the responsibility for
                  administering the disposition of any Shares on account of the
                  Purchaser's death, or any individual who holds such Shares as
                  a legatee, distributee, or successor in interest, or trustee
                  where no executor, administrator, or similar fiduciary is
                  appointed or where any appointed executor, administrator, or
                  fiduciary does not have control over any of the deceased
                  Employee Shareholder's Shares.

         (c)      In the event that an Employee Shareholder desires to sell,
                  assign or otherwise transfer all or any part of his or her
                  Shares or if his or her Shares are subject to an involuntary
                  transfer incident to a divorce or bankruptcy, the Employee
                  Shareholder shall first comply with the following procedures:

                  (i)      The Employee Shareholder shall deliver to the Company
                           a written notice of intention to transfer the Shares
                           (the "Transfer Notice") which shall specify the
                           number of Shares (the "Subject Shares") that the
                           Employee Shareholder desires to transfer and such
                           information regarding the identity of the proposed
                           transferee as the Company shall require.

                  (ii)     Upon receipt of the Transfer Notice, the Company
                           shall have a period of 30 days (the "Company Purchase
                           Period") to redeem and repurchase the Subject Shares
                           at a per Share price equal to the greater of (1) the
                           Per Share Earnings multiplied by 3 or (2) the book
                           value of a Share on the date of repurchase by the
                           Company determined in accordance with generally
                           accepted accounting principles. If the Company
                           notifies the Employee in writing, on or before the
                           30th day of the Company Purchase Period, that it
                           intends to redeem and repurchase the Subject Shares,
                           then the Employee Shareholder shall tender the
                           Subject Shares, and the Company shall pay the price
                           set forth above, in the manner described in
                           Subsection (i), (ii) and (iii) of subsection (a) of
                           this Section 3.

                  (iii)    If the Company does not notify the Employee
                           Shareholder in writing that it intends to redeem and
                           repurchase the Subject Shares on or before the 30th
                           day of the Company Purchase Period, then the Employee
                           Shareholder shall be permitted, for a period of 30
                           days after the expiration of the Company Purchase
                           Period, to sell, assign or transfer the Subject
                           Shares to the proposed transferee identified in the
                           Transfer Notice, subject to the

                                      -12-
<PAGE>

                           transfer restrictions described in this Article II.
                           The transferee shall, as a condition of such a sale,
                           assignment or transfer of Shares, execute an
                           agreement substantially identical in form to this
                           Agreement (other than Article I) which may be
                           accomplished by a certificate of acceptance and
                           adoption of this Agreement (other than Article I).

                  (iv)     If the Employee Shareholder shall fail to sell,
                           assign or transfer any or all of the Subject Shares
                           to the proposed transferee identified in the Transfer
                           Notice on or before the 30th day following the
                           Company Purchase Period, then the Employee
                           Shareholder shall not be permitted to sell, assign or
                           otherwise transfer any Subject Shares not sold,
                           assigned or transferred during such 30-day period
                           unless the Purchaser first provides the Company with
                           a new Transfer Notice and again complies with the
                           procedures of this subsection (c).

         4.       INVALIDITY OF TRANSFERS WHICH WOULD TERMINATE COMPANY'S STATUS
AS S CORPORATION. Notwithstanding anything herein contained to the contrary, no
Shareholder shall transfer any of his Shares, or any interest therein if, as a
result of such transfer, any of the following occurs:

         (a)      The Company's status as an S Corporation would terminate.
                  Without limiting the generality of the foregoing, no
                  Shareholder shall transfer any of his, her or its Shares to,
                  and no Shares shall be acquired by, any person falling within
                  any of the following categories:

                  (i)      A non-resident alien;

                  (ii)     A corporation, a partnership or a trust which does
                           not satisfy the requirements of Code
                           Sections 1361(c)(2), (c)(6), (d) or (e), or their
                           successor provisions; or

                  (iii)    Any other person or entity, a transfer to whom or
                           which would result in the termination of the
                           Company's election to be taxed as an S Corporation
                           under the applicable Internal Revenue Code
                           provisions.

         (b)      Moreover, no Shareholder may transfer any of his, her or its
                  Shares so as to cause the total number of "shareholders" of
                  the Corporation, as determined under Section 1361(c) of the
                  Internal Revenue Code, to exceed seventy-five (75), or such
                  larger number as may at that time be permitted for S
                  Corporations by applicable Internal Revenue Code sections or
                  Internal Revenue Service regulations.

         5.       ATTEMPTED TRANSFERS IN VIOLATION OF SHARE TRANSFER
RESTRICTIONS. Any purported transfer of Shares in violation of this Article II
shall be null and void and shall have no legal effect. An attempt to transfer an
interest in the Shares of the Company in violation of this Agreement shall be
ineffective and the Company shall refuse to register the Shares in question in
the name of the transferee. Any Shareholder who causes or authorizes a
revocation or transfer that terminates the Company's S election in violation of
Section 1362(a) of the Code (whether in

                                      -13-
<PAGE>

his, her, or its capacity as a Shareholder, director, officer, employee or agent
for the Company or otherwise) shall be liable to the Company and to every other
Shareholder for any and all damages, liabilities or costs resulting directly and
indirectly therefrom, including, without limitation, any additional federal or
state tax liability incurred by the Corporation or any other Shareholder as a
result of the improper revocation or termination and any attorneys' fees or
other costs incurred in computing and collecting any such damages; provided,
however, that no Shareholder shall be liable for damages under this Section 5
for making a transfer that terminates the election if the Shareholder acted,
after obtaining a written waiver from the Company's Board of Directors, in
compliance with this Agreement. The additional federal and state tax liability
caused by the improper revocation or termination shall be computed by the
accountant that regularly prepares the Company's tax returns and such
accountant's determination of such liability shall, except as otherwise provided
in this action, be conclusive and binding on all parties hereto for all
purposes.

         6.       INADVERTENT TERMINATION OF S CORPORATION ELECTION. In the
event that the Company's election to be taxed as an S Corporation is terminated,
except in accordance with this Agreement, the Corporation shall immediately seek
a waiver of such termination from the Internal Revenue Service under Sections
1362(f)(3) and 1362(f)(4) of the Internal Revenue Code, and each Shareholder
agrees to take any action as may be required by the Internal Revenue Service to
obtain such a waiver. The Company shall bear the expense of procuring the
waiver, including the legal, accounting and tax costs of taking such steps and
of making such adjustments as may be required, except to the extent that
Shareholders are required to bear such costs, or any portion of such costs, as a
condition to receiving the waiver. If the Company fails to receive such a
waiver, the Company shall request the consent of the Internal Revenue Service to
re-file an election to be taxed as an S Corporation prior to the time specified
in Section 1362(g) of the Code, and each Shareholder agrees to take any action
as may be required to obtain the consent of the Internal Revenue Service to such
an early re-election by the Corporation to be taxed as an S Corporation.

         7.       SOTSEKS OPTION. Notwithstanding anything to the contrary in
this Agreement, at such time as Sotseks shall have distributed OSO Units to
persons entitled to become shareholders of the Company pursuant to the
provisions of Code Section 1361(b) or its successor provisions, such persons
shall have the right to transfer all or part of the OSO Units to the Company in
exchange for a number of non-voting OFS Shares equal to 1,000 times the number
of OSO Units which shall be exchanged, subject to appropriate adjustments for
stock splits, stock dividends, recapitalizations and similar events occurring
after the date hereof which may affect the OFS Shares. The Company agrees to
issue the OFS Shares to which such persons would be entitled upon such an
exchange when it receives an appropriate assignment of the OSO Units and
customary representations and warranties from such persons and, if necessary,
from Sotseks as to such exchange.

                          ARTICLE III - DISTRIBUTIONS

         1.       DISTRIBUTION OF NET CASH FLOW TO MEET ESTIMATED TAX
OBLIGATIONS. Except in connection with the dissolution and liquidation of the
Company and except as prevented by applicable state law, a dividend distribution
shall be made to each Shareholder, no later than January 1, April 1, June 1 and
September 1 of each year in an amount equal to 43% of the

                                      -14-
<PAGE>

estimated income attributable to the pro rata shares of the Company's net long
term and Section 1231 capital gains and non-separately stated items of income
pursuant to Section 1366(a) of the Internal Revenue Code, as amended (as
determined by the Board of Directors of the Company) for the applicable periods
for which estimated federal and state income tax payments must be made by the
Shareholder and, to the extent feasible, all loan agreements and other
arrangements with lenders shall contain a reservation of right on the part of
the Company to make such payments.

         2.       DISTRIBUTION PROCEDURE. Distributions shall be made to
Shareholders (or to their estates, personal representatives, successor or
assigns, as appropriate) of record on the record date for the dividend
distribution, regardless of whether they hold Shares on the date of
distribution. Any pro rata dividend distributions made during the taxable year
in question to shareholders in excess of 43% of actual tax distribution made in
Section 1 above for the applicable periods can be taken into account in
determining the extent of the future minimum mandatory dividends for the balance
of a taxable year.

         3.       DISTRIBUTIONS IN THE EVENT OF TERMINATION OF S CORPORATION
STATUS. It is the intent of this Article III to protect Shareholders to the
extent allowed by law and the Company's financing agreements, against the
possibility that they may be subjected to federal or state income taxes based
upon income of the Company for taxable periods but not have adequate payments
from the Company to satisfy such taxes or a timely basis, and to require the
Company to make periodic payments to the Shareholders in the form of dividends
in amounts sufficient to allow them to pay such taxes. In the event that the
status of the Company as an S Corporation terminates for any reason, the Company
shall nonetheless pay sufficient dividends to permit Shareholders to pay any
such taxes attributable to the period prior to the termination of such status.

         4.       ALLOCATIONS. Allocations of income, gain, deduction and loss
shall be made on a pro rata basis to all persons who were Shareholders at any
time during the taxable year on a per share per diem basis in accordance with
Section 1377(a) of the Internal Revenue Code, or in accordance with such other
methodology as may be permitted by the Code. To the extent permitted under
Section 1377(a)(2), by signing below or subsequently agreeing to be bound by
this Agreement (other than Article I), the "affected Shareholders" hereby
consent in advance to any Company closing of the books election whenever the
Company's Board of Directors deems it appropriate to make such an election.

                        ARTICLE IV - GENERAL PROVISIONS

         1.       ENTIRE AGREEMENT. This Agreement, including any document
delivered by the Company, OSO, or the Unitholders in accordance herewith,
constitutes the entire agreement and supersedes all prior agreements and
understandings, oral and written, between the parties to this Agreement with
respect to the subject hereof.

         2.       BENEFITS; ASSIGNMENT. This Agreement will inure to the benefit
of the parties to this Agreement and shall be binding upon them and their
respective successors and assigns. Neither this Agreement nor any right, remedy,
obligation or liability arising hereunder or by reason hereof shall be
assignable by either the Company, OSO, a Unitholder, or a Shareholder

                                      -15-
<PAGE>

without the prior consent of the other parties, except to the extent it is
assigned in connection with transfers of Shares or OSO Units permitted
hereunder.

         3.       GOVERNING LAW. The parties to this Agreement agree that this
Agreement shall be construed as to both the validity and performance and shall
be enforced in accordance with and governed by the laws of the State of Indiana.

         4.       LEGEND ON STOCK CERTIFICATES. The certificates for Company
Shares to be acquired by the Unitholders at the Closing shall be endorsed as
follows:

         This certificate is transferable only in compliance with the provisions
         of the Exchange Agreement dated as of September 23, 2003, affecting the
         shares represented hereby, a copy of which is on file in the office of
         the Secretary of the Company.

         The securities represented by this certificate have not been registered
         under the Securities Act of 1933, as amended, or the securities laws of
         any state. As a result, the securities represented by this certificate
         may not be sold or transferred in the absence of registration under
         such laws or an opinion from legal counsel satisfactory to the Company
         that such registration is not required.

All certificates for Shares hereafter issued to the Shareholders shall bear the
same endorsement. The legend concerning the Exchange Agreement shall be removed
from the certificates following termination of this Agreement.

         5.       AMENDMENT. This Agreement may be amended prior to the Closing
Date only by unanimous agreement of the Unitholders, the Company, and OSO. From
and after the Closing Date, this Agreement may be amended for the sole purpose
of reflecting a transfer of Shares made in accordance with the terms of the
Agreement by a written amendment signed only by the Company and the transferee.
This Agreement may also be amended by the Company's Board of Directors (a)
solely for the purpose of clarification without substantive change, and (b) if
the amendment is, in the opinion of counsel for the Company, necessary or
appropriate to satisfy current requirements of the Internal Revenue Code with
respect to S Corporations or any federal or state securities laws or
regulations. Shareholders will be notified of any such amendments not requiring
Shareholder approval. No other amendment or modification of this Agreement shall
be valid unless it is approved by the Company's directors, is in writing and
signed by Shareholders holding 100% of the Company's voting Shares then
outstanding, and is duly executed by the Company. Except as to amendments for
the sole purpose of reflecting a transfer of Shares made in accordance with the
terms of this Agreement, all Shareholders shall be given written notice at least
five (5) business days in advance of the effective date of any proposed
amendment.

         6.       TERM. This Agreement may be terminated at any time prior to
the Closing Date by the Company or by OSO. Following the Closing, Articles II
and II of this Agreement shall terminate, and the certificates representing
Shares subject to this Agreement shall be released from the restrictions on
transferability set forth in Article II hereof, by written agreement signed by
the Company and Shareholders owning not less than 100% of the Company's voting
Shares then outstanding. Articles II and III of this Agreement shall also
terminate if, notwithstanding

                                      -16-
<PAGE>

the good faith efforts of all parties, the status of the Company as an S
Corporation is finally and irrevocably terminated, by operation of law or
otherwise, or if the Company closes a public offering of its Shares in a
transaction that results in more than 75 shareholders or in nonqualifying S
Corporation shareholders. Upon the termination of this Agreement, each
Shareholder shall surrender to the Company the certificates for his, her or its
Shares, and the Company shall issue to such Shareholder new certificates for an
equal number of Shares without the legend concerning the Exchange Agreement set
forth in section 4 of this Article IV.

         IN WITNESS WHEREOF, this Agreement was executed by the Company and the
Unitholders as of the date first written above.

OAK STREET OPERATIONS LLC                   OAK STREET FINANCIAL SERVICES, INC.

By:     /s/ Steve Alonso                       By:    /s/ Steve Alonso
-------------------------------                --------------------------------
    Steve Alonso, President                     Steve Alonso, President

UNITHOLDERS:

        /s/ Steve Alonso                              /s/ John F. Havens
-------------------------------                --------------------------------
Steven Alonso                                   John F. Havens

        /s/ Ellen H. Hardymon                         /s/ John C. Havens
-------------------------------                --------------------------------
Ellen H. Hardymon                               John C. Havens

                                      -17-
<PAGE>

/s/ Thomas F. Havens                     National City Bank, Agent U/A with
Thomas F. Havens                         Suzanne H. Nick

                                         By: /s/ Edwin E. Edwards III
National City Bank, Agent U/A with           Edwin E. Edwards III, Trust Manager
Thomas F.Havens
                                         By: /s/ Ellen H. Hardymon
 By: /s/ Edwin E. Edwards III                Ellen H. Hardymon, Special Trustee
     Edwin E. Edwards III, Trust Manager
                                          /s/ George A. Skestos
 By: /s/ John F. Havens                   George A. Skestos
     John F. Havens, Special Trustee

 By: /s/ Philipp D. Nick                  /s/ Glenn R. Brunker
     Philipp D. Nick, Special Trustee     Glenn R. Brunker*

 By: /s/ Patrick J. Dugan                 /s/ Mike Keleher
     Patrick J. Dugan, Special Trustee    Mike Keleher*

/s/ D. Scott Clark
D. Scott Clarke*                          /s/ Dennis L. Trent
                                          Dennis L. Trent*

/s/ Leah B. Grinnen
Leah B. Grinnen*                          /s/ Michael Brown
                                          Michael Brown*

/s/ Craig L. Royal
Craig L. Royal*                           /s/ Charles W. Steadman
                                          Charles W. Steadman*
/s/ George Rossman II
George Rossman II*                        /s/ Paul F. Plaia
                                          Paul F. Plaia*
/s/ Deborah Cowan
Deborah Cowan*                            SOTSEKS CORP.

/s/ Deborah Dawson                        /s/ George A. Skestos
Deborah Dawson*
                                          By:
/s/ Mike Ford
Mike Ford*

*Employee Shareholders

                                       18
<PAGE>
                      AMENDMENT NO. 1 TO EXCHANGE AGREEMENT

         This AMENDMENT NO. 1 TO EXCHANGE AGREEMENT, dated as of April 30, 2004
(the "Amendment"), amends that certain Exchange Agreement, dated as of September
23, 2003 (the "Exchange Agreement"), entered into by and among Oak Street
Financial Services, Inc., a Maryland corporation (the "Company"), Oak Street
Operations LLC, a Delaware limited liability company ("OSO") and the
then-existing unitholders ("Unitholders") of Oak Street Mortgage LLC, a Delaware
limited liability company ("OSM").


                                    RECITALS

         A. The Company, OSO and the then-existing unitholders of OSM entered
into the Exchange Agreement pursuant to which (i) all of the members of OSM
exchanged their OSM ownership units for OSO ownership units, and (ii) all of the
OSO unitholders other than Sotseks Corp. exchange their OSO ownership units for
shares of the Company's common stock.

         B. The Company's Board of Directors has authorized this Amendment
pursuant to Section 5 of the Exchange Agreement solely to clarify the intent of
the parties with regard to the effective date, for accounting purposes, of the
transactions described therein.


                                    AMENDMENT

     1.  The Exchange Agreement is hereby amended by replacing the first
         introductory paragraph thereof, in its entirety, with the following:

         "THIS EXCHANGE AGREEMENT, dated as of September 23, 2003, is by and
         among Oak Street Financial Services, Inc., a Maryland corporation (the
         "Company"), Oak Street Operations LLC, a Delaware limited liability
         company ("OSO") and unitholders ("Unitholders") of Oak Street Mortgage
         LLC, a Delaware limited liability company ("OSM"), to be effective for
         accounting purposes as of the close of business on September 30, 2003,
         so that the results of operations and financial position shall be
         included in the Company's consolidated financial statements beginning
         September 30, 2003 as if the transactions set forth herein were
         effective September 30, 2003."

     2.  Except as set forth herein, all other terms and provisions set forth in
         the Exchange Agreement remain in full force and effect.

         IN WITNESS WHEREOF, this Amendment was executed by the undersigned as
of the date first written above.


                                       OAK STREET FINANCIAL SERVICES, INC.


                                        /s/ Steven Alonso
                                       -------------------------------------
                                       By: Steven Alonso
                                       President and Chief Executive Officer