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                                                                   Exhibit 10.56

                                January 16, 2001

Polar Molecular Corporation
4600 S. Ulster
Suite 700
Denver, CO 80237

     Attn: Mark L. Nelson, Chairman, President and Chief Executive Officer

Gentlemen:

     The purpose of this letter (this "Letter Agreement") is to confirm the
engagement of APS Financial Corporation, a Colorado corporation ("APS
Financial") to act as exclusive placement agent to Polar Molecular Corporation
(the "Company") in connection with a proposed private placement (the "Bridge
Placement') of the Company's ten percent (10%) Cumulative Redeemable Preferred
Stock (together with the related stock purchase warrants described below, the
"Bridge Securities"). Furthermore, if aggregate subscriptions of at least
$350,000 (the "Minimum Bridge Subscriptions") are received in the Bridge
Placement, then, pursuant to this Letter Agreement, APS Financial will also act
as exclusive placement agent to the Company in connection with a subsequent
proposed private placement (the "Secondary Placement") of shares of the
Company's preferred stock subject to the terms and conditions of this Letter
Agreement. The Bridge Securities and the stock and purchase warrants offered in
the Secondary Placement are collectively referred to herein as the "Securities."
As used in this Letter Agreement, "subscriptions" means the tender to the
Company of properly completed subscription documents, prepared in accordance
with Section 1.3, that have been executed by the subscribing investor and which
include tender of payment in accordance with the terms of such subscription
documents.

     1. Engagement. It is expressly understood and acknowledged that APS
Financial's engagement hereunder does not constitute any commitment, expressed
or implied, on the part of

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Polar Molecular Corporation
January 16, 2001
Page 2

APS Financial to purchase or place the Securities and that the placements of the
Securities by APS Financial will be made on a "best efforts" basis.

          1.1 Bridge Placement. The Company will offer, on an exclusive basis,
     through APS Financial, up to $750,000 of the Bridge Securities. The Bridge
     Securities will consist of units comprised of the Company's ten percent
     (10%) Cumulative Redeemable Preferred Stock together with warrants
     entitling the holders thereof to purchase, such number of shares of common
     stock of the Company as is equal to four and four-hundredths percent
     (4.04%) of the fully diluted outstanding shares of common stock of the
     Company as of the conclusion of the Bridge Placement; it being understood
     that the calculation of full dilution shall include all outstanding common
     stock warrants, options, conversion and other acquisition rights of any
     kind (including without limitation royalties, debt, interest, compensation,
     Series A Preferred stock and consulting-related conversions into equity),
     as well as the Bridge Securities sold in the Bridge Placement and all
     potential shares issuable under the new proposed fifteen percent (15%)
     officer and director option plan (collectively referred to hereafter as
     "Fully Diluted Shares"). The total options to be available for award under
     such officer and director option plan shall equal fifteen percent (15%) of
     the Fully Diluted Shares (inclusive of those to be included in the option
     plan itself). The price for the Bridge Securities (the "Bridge Price") will
     be agreed upon by APS Financial and the Company prior to soliciting offers
     for the Bridge Placement. The warrants shall expire five (5) years after
     the close of the first Public Offering (as hereinafter defined). The Bridge
     Securities shall have such other terms as set forth on Exhibit A hereto,
     and as otherwise may be agreed upon by APS Financial and

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Polar Molecular Corporation
January 16, 2001
Page 3

     the Company. Furthermore, purchasers of the Bridge Securities shall receive
     incidental "piggyback" registration rights with respect to the Company
     common stock obtainable by them, through exercise of warrants, conversion,
     dividend or otherwise, that will be pari passu with the registration rights
     granted to APS Financial and the purchasers of the Secondary Securities (as
     hereinafter defined), and senior to all other registration rights. In
     addition, upon the vote of a majority-in-interest of the holders of the
     Bridge Securities after the Company has had net operating income of at
     least $1,250,000 for a fiscal quarter, the holders of the Bridge Securities
     shall be entitled to demand a public registration of their shares.
     Purchasers of the Bridge Securities will enter into one or more agreements
     with the Company entitling them to information, redemption/repurchase and
     other contractual rights including, without limitation, rights to convert
     the Bridge Securities into securities in the Secondary Placement, and a
     pledge by the Company to the purchasers of the Bridge Securities of a
     security interest in and to all assets, rights and properties of any kind
     of the Company to secure the Company's performance of its obligations under
     such contractual agreements and under the terms of the Bridge Securities
     themselves.

          1.2 Secondary Placement. For purposes of this Letter Agreement,
     "Bridge Placement Deadline" means the first business day upon which both of
     the following conditions are satisfied: (i) five (5) business days have
     elapsed since the Company has complied with its pre-Closing obligations
     under Sections 1.3 and 5 as they relate to the Bridge Placement, and (ii)
     the Company is able to close the sale of the Bridge Securities to full
     compliance with applicable contractual agreements related thereto.

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Polar Molecular Corporation
January 16, 2001
Page 4

          In the event Minimum Bridge Subscriptions are received by the Company
     on or before the Bridge Placement Deadline, then APS Financial shall also
     act as exclusive placement agent to the Company in connection with an
     offering of up to $4,000,000 of units comprised of Preferred Stock and
     common stock purchase warrants (collectively, the "Secondary Securities")
     as set forth generally on Exhibit B hereto and with such further rights and
     preferences as may be agreed upon by APS Financial and the Company. The
     Secondary Placement will close thirty (30) calendar days after the Minimum
     Secondary Deadline (as hereinafter defined), unless otherwise agreed by APS
     Financial and the Company. The parties acknowledge and agree that the
     provisions contained on Exhibit B are preliminary only at this time and are
     subject to further refinement as may be mutually agreed upon as the
     commencement date of the offering approaches.

          1.3 Compliance Requirements. It is understood and agreed that, in
     connection with the Bridge Placement and Secondary Placement, it shall be
     the obligation of the Company to (i) prepare, and provide an adequate
     supply of, offering memoranda, subscription materials, purchase agreements
     and related contractual agreements and other related documentation
     (collectively, the "Offering Materials") all of which must be reasonably
     acceptable in form and substance to APS Financial, and (ii) qualify the
     sales of the Securities (through filing, securing an exemption or other
     required action) with the Securities and Exchange Commission (the "SEC")
     and under any applicable state securities law or agency. Upon receipt of an
     acceptable written opinion of legal counsel

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Polar Molecular Corporation
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     to the Company, the requirement of an offering memorandum in connection
     with the Bridge Placement will be waived.

          1.4 Company Representations and Covenants. The Company represents and
     warrants that this Letter Agreement and the transactions contemplated
     hereunder do not violate, conflict with, or, except as set forth on Exhibit
     C, give rise to any potential right of first refusal to purchase the
     Securities, or constitute a default under, the terms, conditions or
     provisions of any contract to which the Company or any of its affiliates is
     a party, including, without limitation, any underwriting contracts,
     exclusivity contracts, investor rights agreements or rights of first
     refusal. The Company agrees to indemnify and hold harmless APS Financial
     and each purchaser of Securities from and against any losses, costs,
     expenses or claims, in whole or in part, based on, relating to or arising
     out of, any of the contracts or transactions described on Exhibit C.

          The Company, and its affiliates, have not taken, and will not take,
     any action, directly or indirectly, that may cause the Bridge Placement or
     Secondary Placement to fail to be entitled to exemption from registration
     under federal or applicable state securities laws or "blue sky" laws.

          1.5 Announcements. APS Financial may, at its own expense, place
     announcements or advertisements in financial newspapers and journals
     describing its services hereunder.

          1.6 Future Transactions.

               A. If any persons or entities introduced to the Company by APS
          Financial make an investment in the Company, whether in the form of
          debt,

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Polar Molecular Corporation
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          equity or otherwise, on or before December 31, 2003, APS Financial
          will be paid fees with respect to each such investment (and receive
          such additional non-cash compensation such as warrants, etc.)
          calculated on the same basis as was applicable to the then most recent
          prior offering in which APS Financial was entitled to fees or other
          compensation with respect to its services in connection with such
          offering. If any person or entity that subscribes for any of the
          Securities are not introduced to the Company by APS Financial (a
          "Company Investor"), and any Company Investor thereafter makes an
          investment in the Company on or before December 31, 2002, whether in
          the form of debt, equity or otherwise, APS Financial will be entitled
          to receive, at the closing of each such investment, warrants entitling
          APS Financial, its employees, affiliates, agents or representatives
          and their respective assigns or successors to exercise an option to
          purchase, in whole or in part at any time, and from time to time, such
          number of shares of common stock of the Company as is equal to five
          percent (5%) of the total common stock acquired or acquirable (through
          the conversion of preferred stock, exercise of warrants or options, or
          otherwise) by each such Company Investor. The warrants shall be
          exercisable until the fifth (5th) anniversary of the close of the
          first Public Offering (as hereinafter defined), and the exercise price
          per share shall be the purchase price per share of common stock
          implicit in the applicable investment by the Company Investor. The
          warrants shall have such other terms and conditions as the Bridge
          Placement Warrants described in Section 2.2. The Company agrees to
          promptly (and in any event prior to

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Polar Molecular Corporation
January 16, 2001
Page 7

          accepting any sales proceeds) notify APS Financial in writing if it
          believes any investor is a Company Investor, and if the parties are
          not able to agree on the status of an investor for purposes of this
          paragraph then either party my submit the dispute to arbitration as
          set forth in Section 6. If APS Financial is not timely notified by the
          Company as provided in the preceding sentence, then the investor will
          be deemed to have been introduced by APS Financial.

               B. "Minimum Secondary Deadline" means the first business day on
          which all of the following conditions are satisfied: (i) forty-five
          (45) calendar days have elapsed since the Company has complied with
          its pre-Closing obligations under Sections 1.3 and 5 as they relate to
          the Secondary Placement, (ii) the Company is able to close the sale of
          the Secondary Securities in full compliance with applicable
          contractual agreements related thereto, and (iii) the Company is in
          compliance with its contractual obligations to APS Financial and the
          purchasers of the Bridge Securities. In the event that a minimum of
          $2,000,000 in subscriptions are received by the Company in the
          Secondary Placement ("Minimum Secondary Subscriptions") on or before
          the Minimum Secondary Deadline, the APS Financial shall have a right
          of first refusal to serve as exclusive placement agent with respect to
          the next offering of at least $2,000,000 (other than a Public
          Offering) on terms and conditions mutually agreeable to the Company
          and APS Financial, but in no event shall the compensation to APS
          Financial (both cash and non-cash compensation in the form of
          warrants, etc.) be less than eighty percent (80%) of the rates of

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January 16, 2001
Page 8

          compensation provided for with regard to the Secondary Placement
          unless agreed upon by APS Financial in its sole discretion.
          Notwithstanding the preceding sentence, with respect to any offerings
          of at least $2,000,000 on or before December 31, 2002 in which the
          Company is paying no form of compensation whatsoever to any broker,
          finder or other type of agent (a "Direct Investment"), APS Financial's
          right of first refusal described above shall not apply and, in lieu
          thereof, APS Financial shall be entitled to receive warrants entitling
          APS Financial, its employees, affiliates, agents or representatives
          and their respective assigns or successors to exercise an option to
          purchase, in whole or in part at any time, and from time to time, such
          number of shares of common stock of the Company as is equal to five
          percent (5%) of the total common stock acquired or acquirable (through
          the conversion of preferred stock, exercise of warrants or options, or
          otherwise) by the investors in each such Direct Investment. The
          warrants shall be exercisable until the fifth (5th) anniversary of the
          close of the first Public Offering, and the exercise price per share
          shall be the purchase price per share of common stock implicit in the
          applicable Direct Investment. The warrants shall have such other terms
          and conditions as the Bridge Placement Warrants described in Section
          2.2. Receipt of warrants by APS Financial with respect to Direct
          Investments shall not terminate or otherwise affect APS Financial's
          right of first refusal set forth in this paragraph. If APS Financial
          elects not to exercise its right of first refusal with respect to an
          offering to which it applies, then the right of first refusal will
          terminate with respect to any future

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Polar Molecular Corporation
January 16, 2001
Page 9

          offering; provided APS Financial will continue to be entitled to
          participate in a Public Offering pursuant to subsection C below. A
          "Public Offering" is an underwritten public offering of the Company's
          common stock pursuant to a registration statement filed with, and
          declared effective by, the SEC.

               C. In the event Minimum Secondary Subscriptions are received by
          the Company by the Minimum Secondary Deadline, then if the Company
          undertakes a Public Offering, the Company agrees that APS Financial
          shall be entitled to be included as an underwriter therein for no less
          than twenty percent (20%) of the total maximum amount of such
          offering. Any related underwriting agreement shall be on terms and
          conditions mutually agreeable to the parties: provided the
          compensation to APS Financial thereunder shall be no less favorable
          than that applicable to the lead underwriter (including management
          fees, selling concessions and all other forms of compensation to the
          lead underwriter). APS Financial's rights to be included in a public
          offering pursuant to this paragraph shall only apply to the first
          applicable offering.

               D. In the event Minimum Bridge Subscriptions are received by the
          Company on or before the Bridge Placement Deadline, then the
          provisions of subsection A of this Section 1.6 shall survive any
          termination or expiration of this Letter Agreement. In the event
          Minimum Secondary Subscriptions are received by the Company on or
          before the Minimum Secondary Deadline, then the provisions of
          subsections B. and C. of this Section 1.6 shall survive any
          termination or expiration of this Letter Agreement.

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Polar Molecular Corporation
January 16, 2001
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     2. Fees and Expenses. As compensation for APS Financial's services
hereunder, the Company hereby agrees to pay and deliver, promptly upon receipt
of any proceeds from sales of the Securities, to APS Financial, the fees, shares
and warrants as follows:

          2.1 Cash Fees. A Cash Placement Fee equal to five percent (5%) of the
     total amount of gross proceeds received for Bridge Securities. With respect
     to the Secondary Placement, APS Financial shall be paid a selling
     concession of eight percent (8%), a due diligence fee of four percent (4%)
     and an unaccountable expense reimbursement of three percent (3%), in each
     case based on the total gross proceeds from the Secondary Placement. Bridge
     Securities converted into the Secondary Placement will be treated as
     proceeds from the Secondary Placement for fee purposes.

          2.2 Bridge Placement Warrants. Warrants (the "Bridge Placement
     Warrants") entitling APS Financial, its employees, affiliates, agents, or
     representatives, and their respective assigns or successors, to exercise an
     option to purchase, in whole or in part at any time, and from time to time,
     on or prior to the fifth (5th) anniversary of the close of the first Public
     Offering, such number of shares of common stock of the Company as is equal
     to two and two-hundredths percent (2.02%) of the fully diluted outstanding
     shares of common stock of the Company as of the conclusion of the Bridge
     Placement. The exercise price, and other terms and conditions of the Bridge
     Placement Warrants, shall be the same as the warrants included in the
     Bridge Securities. Full dilution will be calculated on the same basis as
     described in Section 1.1 and shall include, without limitation, all shares
     issued or issuable in the Bridge Placement and to APS Financial with
     respect to the Bridge Placement pursuant to his Letter Agreement. The
     Bridge

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     Placement Warrants shall be delivered promptly upon conclusion of the
     Bridge Placement. All common stock acquirable upon exercise of the Bridge
     Placement Warrants shall be subject to the same type and priority of
     registration rights as provided to purchasers of the Securities pursuant to
     Section 1.1.

          2.3 Monthly Advisory Fees. Subject to the terms of this Section 2.3,
     APS Financial shall be entitled to receive monthly advisory fees in the
     amount of $10,000 per month, beginning with the month of December, 2000 and
     continuing thereafter until the Company completes the first Public
     Offering. The first payment of the monthly amounts due under this Section
     shall be made on April 1, 2001. Thereafter, payment shall be made quarterly
     on the first business day after the calendar quarter to which the payment
     relates. The Company will issue APS Financial common stock in lieu of cash
     to discharge its obligations under this Section at a rate equal to the per
     share exercise price of the Bridge Placement Warrants; provided that if
     subscriptions totaling $4,000,000 or more are received by the Company in
     the Secondary Placement, then one-half of each subsequent month's advisory
     fees will be paid in cash and the remainder shall be paid in Company common
     stock at the rate equal to the per share exercise price of the warrants
     described in Section 2.4.

          2.4 Secondary Placement Warrants. Warrants entitling APS Financial,
     it's employees, affiliates, agents, or representatives, and their
     respective assigns or successors, to exercise an option to purchase, in
     whole or in part at any time, and from time to time, on or prior to the
     fifth (5th) anniversary of the close of the first Public Offering, such
     number of common shares of the Company as is equal to fifteen percent

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Polar Molecular Corporation
January 16, 2001
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     (15%) of the total maximum amount of common shares that holders of the
     Secondary Securities may acquire, by conversion, exercise of warrants, or
     otherwise, at the conclusion of the Secondary Placement. The exercise price
     per share shall be the purchase price per share of common stock implicit in
     the Secondary Placement, and the other terms and conditions of the
     warrants, shall be the same as the Bridge Placement Warrants. All common
     stock acquirable upon exercise of the warrants (and all other common stock
     acquirable by APS Financial under the terms of this Letter Agreement) shall
     be subject to the same type and priority of "piggyback" registration rights
     as provided to purchasers of the Securities pursuant to Section 1.1

          2.5 Expenses. The Company shall reimburse APS Financial for the fees
     and expenses of legal counsel to APS Financial incurred in connection with
     the Bridge Placement and the Secondary Placement, up to a maximum of
     $25,000 for each such placement. The Company shall reimburse APS Financial
     for such expenses related to the Bridge Placement upon receiving Minimum
     Bridge Subscriptions on or before the Bridge Placement Deadline; and shall
     reimburse APS Financial for expenses related to the Secondary Placement
     upon receiving Minimum Secondary Subscriptions on or before the Minimum
     Secondary Deadline.

     3. Board Positions. As soon as the Company receives the Minimum Bridge
Subscriptions, and thereafter until the end of the first fiscal year that begins
after the close of the first Public Offering, the Company shall elect, or cause
the election of, two representatives selected by APS Financial to the Company's
Board of Directors. Such directors shall be entitled to reimbursement of all
reasonable travel and lodging expenses incurred in attending meetings.

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Notwithstanding the foregoing, if in connection with the Secondary Placement, or
any subsequent equity financing by the Company, any investor investing
$1,000,000 or more in such financing desires or demands to be, or have a
representative on, the Company's Board of Directors, then APS Financial will
relinquish one of its Board seats in order to allow the Company to accommodate
such request. The initial APS Financial representatives shall be Bill Searles
and George Conwill. Thereafter, during the period APS Financial is entitled to
designate any directors pursuant to this Section, it shall be entitled to
present any persons it desires to name as replacement Board representatives to
the Company and such persons shall be considered in good faith by the Company
for approval subject to commercially reasonable standards for Board membership;
provided the Company's approval shall not be unreasonably withheld. Furthermore,
in the event an APS Financial Board representative can not attend a Board
meeting, then APS Financial shall be entitled to have substitute representatives
attend or otherwise participate in meetings whenever the current designated
director(s) are unable to do so for a maximum of two successive Board meetings
or two months (whichever is the greater time span).

     4. Indemnification. The Company agrees to indemnify APS Financial and
related persons and affiliates in accordance with the indemnification provisions
attached hereto as Schedule I, the provisions of which are incorporated herein
in their entirety. These indemnity obligations shall survive any expiration or
termination of this Letter Agreement.

     5. Disclosure. The Company recognizes and confirms that APS Financial, in
acting pursuant to this engagement, will be using information in reports and
other information provided by others, including, without limitation, information
provided by or on behalf of the Company, and that APS Financial does not assume
responsibility for and may rely, without independent

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January 16, 2001
Page 14

verification, on the accuracy and completeness of any such reports and
information. The Company hereby warrants that the Offering Materials, and any
other information relating to the Company or the Placements contemplated herein,
will not contain any untrue statement of a material fact or omit to state any
material fact necessary to make the statements contained therein, in the light
of circumstances under which they were made, not misleading. The Company agrees
to provide APS Financial with (i) prompt notice of any material development
affecting the Company or the occurrence of any event or other change known to
the Company that could result in any Offering Materials containing an untrue
statement of a material fact or omitting to state any material fact necessary to
make the statements contained therein, in the light of the circumstances under
which they were made, not misleading, (ii) copies of any financial reports as
soon as reasonably practicable and (iii) such other information concerning the
business and financial condition of the Company as APS Financial may, from time
to time, request. APS Financial will have the right to approve all Offering
Materials and other written communications furnished by or on behalf of the
Company in connection with the Bridge Placement or Secondary Placement and the
Company will cause to be furnished to APS Financial and the purchasers of the
Securities, on the respective closing dates of the Placements, copies of such
opinions of counsel and such other documents, letters, certificates and opinions
as APS Financial or the purchasers may reasonably request in form and substance
reasonably satisfactory to APS Financial and its counsel.

     The Company agrees that any information or advice rendered by APS Financial
or its representatives in connection with this engagement is for the
confidential use of the Company only and, except as otherwise required by law,
the Company will not and will not permit any

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January 16, 2001
Page 15

third party to disclose or otherwise refer to such advice or information in any
manner without APS Financial's prior written consent.

     6. Binding Arbitration. In the event of any dispute relating to this Letter
Agreement, the same shall be referred to three arbitrators for binding
arbitration. The three arbitrators shall be selected, one each, by (i) the
Company, (ii) APS Financial, and (iii) mutual agreement of the two arbitrators
selected by the Company and APS Financial. Each arbitrator shall be a
knowledgeable, independent businessperson or professional. If either the Company
or APS Financial refuse to neglect to appoint an arbitrator within thirty (30)
days after receipt of the written request for arbitration, the initiating party
may appoint a second arbitrator. If the two arbitrators fail to agree on the
selection of a third arbitrator within thirty (30) days of their appointment,
each of them shall name three individuals, of whom the other shall decline two,
and the decision shall be made by drawing lots.

     The Company shall bear and APS Financial shall bear their own expense in an
arbitration including their arbitrator fees and attorneys' fees. The Company and
APS Financial shall each bear half of the expense of the third arbitrator. Any
remaining costs of the arbitration proceedings shall be apportioned by the three
arbitrators.

     The arbitration proceedings shall be conducted in accordance with the
commercial arbitration rules of the American Arbitration Association, except
that the Company and APS Financial shall be entitled to take discovery as
provided under Federal Rules of Civil Procedure Nos. 28 through 36 during a
period of ninety (90) days after the final arbitrator is appointed and the
arbitrators shall have the power to issue subpoenas, compel discovery, award
sanctions and grant injunctive relief. The arbitrators shall be entitled to
retain an independent attorney to

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Polar Molecular Corporation
January 16, 2001
Page 16

advise them as to legal matters. The arbitration hearings shall commence no
sooner than one hundred twenty (120) days after the date the final arbitrator is
appointed and not later than one hundred eighty (180) days after such date. The
arbitration hearing shall be conducted during normal working hours on business
days without interruption or adjournment of more than two (2) days at any one
time or six (6) days in the aggregate. The arbitrators shall decide by a
majority vote of the arbitrators. The arbitrators shall deliver their decision
to the Company and APS Financial in writing within twenty (20) days after the
conclusion of the arbitration hearing, which written decision shall include
detailed findings of fact and conclusions of law. There shall be no appeal from
their written decision, except as permitted by applicable law.

     Any arbitration instituted pursuant to this Section shall be held in
Austin, Texas or such other city that is mutually agreeable to the Company and
APS Financial, with the precise location within such city being as agreed upon
by the Company and APS Financial or, absent such agreement, at a location within
such city designated by the American Arbitration Association's resident manager
in Austin, Texas.

     Notwithstanding any other provision of this Section, nothing contained in
this Letter Agreement shall require arbitration of any issue for which
injunctive relief is properly sought by a party hereto; provided the awarding of
monetary damages may only be made through arbitration. The arbitrators, if they
find that any party has acted in a fraudulent manner with respect to any
representation contained in, or any transaction contemplated by, this Letter
Agreement, may award punitive damages to the victim of such fraudulent conduct.

     7. Termination. Either party shall have the right to terminate this Letter
Agreement, by written notice to the other party, in the event the Minimum Bridge
Subscriptions are not

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Polar Molecular Corporation
January 16, 2001
Page 17

received by the Bridge Placement Deadline or the Minimum Secondary Subscriptions
are not received by the Minimum Secondary Deadline. Unless so terminated, this
Letter Agreement shall remain in effect in accordance with its terms. Upon any
termination or expiration of this Letter Agreement, all provisions which, by
their terms or by necessary implication, are intended to survive termination or
expiration shall thereafter remain binding and enforceable. Without limiting the
foregoing, the parties agree that the provisions of Sections 1.4, 3, 4, 5 and 6,
as well as any obligations to pay or deliver any compensation pursuant to
Sections 1.6 and 2 that was earned prior to expiration or termination, and to
reimburse any expenses incurred prior to expiration or termination pursuant to
Section 2.5, shall survive any expiration or termination of this Letter
Agreement.

     8. Miscellaneous. This Letter Agreement (a) shall be governed by and
construed in accordance with the laws of the State of Texas, regardless of the
laws that might otherwise govern under applicable principles of conflicts of law
thereof, (b) incorporates the entire understanding of the parties with respect
to the subject matter hereof and supersedes all previous agreements should they
exist with respect thereto, (c) may not be amended or modified except in a
writing executed by the Company and APS Financial and (d) shall be binding upon
and inure to the benefit of the Company, APS Financial, the other Indemnified
Parties and their respective successors and assigns. The Company and APS
Financial agree to waive trial by jury in any action, proceeding or counterclaim
brought by or on behalf of either party with respect to any matter whosoever
relating to or arising out of any actual or proposed Placement or the engagement
of or performance by APS Financial hereunder. The Company acknowledges that APS
Financial, in connection with its engagement hereunder, is acting as an
independent

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January 16, 2001
Page 18

contactor with duties owing solely to the Company and that nothing
in this agreement is intended to confer upon any other person any rights or
remedies hereunder or by reason hereof.

     This agreement may be executed in two or more counterparts, each of which
shall be deemed to be an original, but all of which shall constitute one and the
same agreement. Please confirm that the foregoing is in accordance with your
understanding of our agreement by signing and returning to us a copy of this
letter.

                                            Very truly yours,

                                            APS FINANCIAL CORPORATION


                                            By: /s/ George S. Conwill
                                                --------------------------------
                                            Printed Name: George S. Conwill
                                            Title: President


Accepted and agreed to as of the date of this Letter Agreement

POLAR MOLECULAR CORPORATION


By: /s/ Mark L. Nelson
    -----------------------------
Printed Name: Mark L. Nelson
Title: President/CEO