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                                                                   Exhibit 10.32

                           INVESTORS' RIGHTS AGREEMENT

     THIS INVESTORS' RIGHTS AGREEMENT is made as of the 30th day of January,
2001, by and among Polar Molecular Corporation, a Utah corporation ("PMC"), the
investors listed on Schedule A hereto (each of which is herein referred to as an
"Investor") and APS Financial Corporation , a Colorado corporation ("APS
Financial").

                                    RECITALS

     WHEREAS, PMC and the Investors are parties to the Bridge Securities
Purchase Agreement of even date herewith (the "Purchase Agreement") whereby the
Investors will be purchasing units of PMC's securities consisting of shares of
PMC's Series B Preferred Stock (the "Series B Preferred Stock") and common stock
purchase warrants (the "Bridge Warrants") (the "Series B Preferred Stock and the
Bridge Warrants are collectively referred to herein as the "Bridge Securities");
and

     WHEREAS, pursuant to that certain letter agreement with PMC dated January
16, 2001 (the "APS Financial Engagement Letter"), APS Financial has assisted PMC
in the sale of the Bridge Securities and APS Financial and such of its
employees, affiliates, agents and representatives as it may designate
(collectively, including APS Financial, the "APS Financial Holders") will
receive common stock and common stock purchase warrants (the "Bridge Placement
Warrants") that will enable APS Financial to purchase shares of PMC's common
stock; and

     WHEREAS, in order to induce PMC to approve the issuance of the Bridge
Securities Stock, to induce the Investors to invest funds in PMC pursuant to the
Purchase Agreement and to induce APS Financial to assist in the sale of the
Bridge Securities, the Investors, PMC and APS Financial hereby agree that this
Agreement shall govern the rights of the Investors and APS Financial to cause
PMC to register shares of Common Stock issued or issuable to them and certain
other matters as set forth herein;

     NOW, THEREFORE, THE PARTIES HEREBY AGREE AS FOLLOWS:

     1.   Registration Rights. PMC covenants and agrees as follows:

     1.1 Definitions. For purposes of this Section 1:

          (a) The term "Act" means the Securities Act of 1933, as amended.

          (b) The term "Form S-3" means such form under the Act as in effect on
     the date hereof or any registration form under the Act subsequently adopted
     by the SEC that permits inclusion or incorporation of substantial
     information by reference to other documents filed by PMC with the SEC.

          (c) The term "Holder" means any person, including, without limitation,
     any APS Financial Holder, owning or having the right to acquire Registrable
     Securities or any assignee thereof in accordance with Section 1.11 hereof.

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          (d) The term "Initial Offering" means PMC's next firm commitment
     underwritten public offering of its Common Stock under the Act.

          (e) The term "1934 Act" means the Securities Exchange Act of 1934, as
     amended.

          (f) The term "register," "registered," and "registration" refer to a
     registration effected by preparing and filing a registration statement or
     similar document in compliance with the Act, and the declaration or
     ordering of effectiveness of such registration statement or document.

          (g) The term "Registrable Securities" means (i) the Common Stock
     issuable or issued upon conversion of the Series B Preferred Stock or
     pursuant to the provisions of the APS Financial Engagement Letter, or
     issuable or issued upon exercise of the Bridge Warrants or the Bridge
     Placement Warrants and (ii) any Common Stock of PMC issued as (or issuable
     upon the conversion or exercise of any warrant, right or other security
     that is issued as) a dividend or other distribution with respect to, or in
     exchange for, or in replacement of, the shares referenced in (i) above,
     excluding in all cases, however, any Registrable Securities sold by a
     person in a transaction in which his rights under this Section 1 are not
     assigned.

          (h) The number of shares of "Registrable Securities" outstanding shall
     be determined by the number of shares of Common Stock outstanding that are,
     and the number of shares of Common Stock issuable pursuant to then
     exercisable or convertible securities that are, Registrable Securities.

          (i) The term "SEC" shall mean the Securities and Exchange Commission.

     1.2 Request for Registration.

          (a) Subject to the conditions of this Section 1.2, if PMC shall
     receive at any time after it has had net operating income of at least
     $1,250,000 for a fiscal quarter, a written request from the Holders of a
     majority of the Registrable Securities then outstanding (the "Initiating
     Holders"), that PMC file a registration statement under the Act covering
     the registration of Registrable Securities with an anticipated aggregate
     offering price of at least $5,000,000, then PMC shall, within twenty (20)
     days of the receipt thereof, give written notice of such request to all
     Holders, and subject to the limitations of this Section 1.2, use best
     efforts to effect, as soon as practicable, the registration under the Act
     of all Registrable Securities that the Holders request to be registered in
     a written request received by PMC within twenty (20) days of the mailing of
     PMC's notice pursuant to this Section 1.2(a).

          (b) If the Initiating Holders intend to distribute the Registrable
     Securities covered by their request by means of an underwriting, they shall
     so advise PMC as a part of their request made pursuant to this Section 1.2
     and PMC shall include such information in the written notice referred to in
     Section 1.2(a). In such event the right of any Holder to include its
     Registrable Securities in such registration shall be conditioned upon such
     Holder's participation in such underwriting and the inclusion of such
     Holder's

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     Registrable Securities in the underwriting (unless otherwise mutually
     agreed by a majority in interest of the Initiating Holders and such Holder)
     to the extent provided herein. All Holders proposing to distribute their
     securities through such underwriting shall enter into an underwriting
     agreement in customary form with the underwriter or underwriters selected
     for such underwriting by PMC (which underwriter or underwriters shall be
     reasonably acceptable to a majority in interest of the Initiating Holders).
     Notwithstanding any other provision of this Section 1.2, if the underwriter
     advises PMC that marketing factors require a limitation of the number of
     securities underwritten (including Registrable Securities), then PMC shall
     so advise all Holders of Registrable Securities that would otherwise be
     underwritten pursuant hereto, and the number of shares that may be included
     in the underwriting shall be allocated to the Holders of such Registrable
     Securities on a pro rata basis based on the number of Registrable
     Securities held by all such Holders (including the Initiating Holders). Any
     Registrable Securities excluded or withdrawn from such underwriting shall
     be withdrawn from the registration.

          (c) PMC shall not be required to effect a registration pursuant to
     this Section 1.2:

               (i) in any particular jurisdiction in which PMC would be required
          to execute a general consent to service of process in effecting such
          registration, unless PMC is already subject to service in such
          jurisdiction and except as may be required under the Act; or

               (ii) after PMC has effected one (1) registration pursuant to this
          Section 1.2, and such registration has been declared or ordered
          effective; or

               (iii) during the period starting with the date sixty (60) days
          prior to PMC's good faith estimate of the date of the filing of, and
          ending on a date one hundred eighty (180) days following the effective
          date of, a Company-initiated registration subject to Section 1.3
          below, provided that PMC is actively employing in good faith best
          efforts to cause such registration statement to become effective; or

               (iv) if the Initiating Holders propose to dispose of Registrable
          Securities that may be registered on Form S-3 pursuant to Section 1.4
          hereof; or

               (v) if PMC shall furnish to Holders requesting a registration
          statement pursuant to this Section 1.2, a certificate signed by PMC's
          Chief Executive Officer or Chairman of the Board stating that in the
          good faith judgment of the Board of Directors of PMC, it would be
          seriously detrimental to PMC and its stockholders for such
          registration statement to be effected at such time, in which event PMC
          shall have the right to defer such filing for a period of not more
          than ninety (90) days after receipt of the request of the Initiating
          Holders, provided that such right to delay a request shall be
          exercised by PMC not more than once in any twelve (12)-month period.

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     1.3 Company Registration.

          (a) If (but without any obligation to do so) PMC proposes to register
     (including for this purpose a registration effected by PMC for stockholders
     other than the Holders) any of its stock or other securities under the Act
     in connection with the public offering of such securities (other than a
     registration relating solely to the sale of securities to participants in a
     Company stock plan, a registration relating to a corporate reorganization
     or other transaction under Rule 145 of the Act, a registration on any form
     that does not include substantially the same information as would be
     required to be included in a registration statement covering the sale of
     the Registrable Securities, or a registration in which the only Common
     Stock being registered is Common Stock issuable upon conversion of debt
     securities that are also being registered), PMC shall, at such time,
     promptly give each Holder written notice of such registration. Upon the
     written request of each Holder given within twenty (20) days after mailing
     of such notice by PMC in accordance with Section 2.5, PMC shall, subject to
     the provisions of Section 1.3(c), use all reasonable efforts to cause to be
     registered under the Act all of the Registrable Securities that each such
     Holder has requested to be registered.

          (b) Right to Terminate Registration. PMC shall have the right to
     terminate or withdraw any registration initiated by it under this Section
     1.3 prior to the effectiveness of such registration whether or not any
     Holder has elected to include securities in such registration. The expenses
     of such withdrawn registration shall be borne by PMC in accordance with
     Section 1.7 hereof.

          (c) Underwriting Requirements. In connection with any offering
     involving an underwriting of shares of PMC's capital stock, PMC shall not
     be required under this Section 1.3 to include any of the Holders'
     securities in such underwriting unless they accept the terms of the
     underwriting as agreed upon between PMC and the underwriters selected by it
     (unless the terms of such underwriting purport to alter the priority status
     of the registration rights of the Holders of Registrable Securities) and
     enter into an underwriting agreement in customary form with an underwriter
     or underwriters selected by PMC, and then only in such quantity as the
     underwriters determine in their sole discretion will not jeopardize the
     success of the offering by PMC. If the total amount of securities,
     including Registrable Securities, requested by stockholders to be included
     in such offering exceeds the amount of securities sold other than by PMC
     that the underwriters determine in their sole discretion is compatible with
     the success of the offering, then PMC shall be required to (i) exclude all
     shares of capital stock other than Registrable Securities and other than
     shares to be sold by PMC for its own account, and (ii) include in the
     offering only that number of Registrable Securities that the underwriters
     determine in their sole discretion will not jeopardize the success of the
     offering (the securities so included to be apportioned pro rata among the
     selling Holders according to the total amount of securities entitled to be
     included therein owned by each selling Holder or in such other proportions
     as shall mutually be agreed to by such selling Holders), but in no event
     shall (i) the amount of securities of the selling Holders included in the
     offering be reduced below thirty percent (30%) of the total amount of
     securities included in such offering, unless such offering is the initial
     public offering of PMC's securities, in which case the selling Holders may
     be excluded if the underwriters make

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     the determination described above and no other stockholder's securities are
     included, or (ii) notwithstanding (i) above, any shares being sold by a
     stockholder exercising a demand registration right pursuant to Section 1.2
     be excluded from such offering. For purposes of the preceding parenthetical
     concerning apportionment, for any selling stockholder that is a Holder of
     Registrable Securities and that is a partnership or corporation, the
     partners, retired partners and stockholders of such Holder, or the estates
     and family members of any such partners and retired partners and any trusts
     for the benefit of any of the foregoing persons shall be deemed to be a
     single "selling Holder," and any pro rata reduction with respect to such
     "selling Holder" shall be based upon the aggregate amount of Registrable
     Securities owned by all such related entities and individuals.
     Notwithstanding the foregoing, in no event will any Registrable Securities
     be excluded from an offering unless all other shares of capital stock of
     any kind, other than those to be sold by PMC for its own account, are first
     excluded; it being understood and agreed that the Holders of Registrable
     Securities have first priority registration rights.

     1.4 Form S-3 Registration. In case PMC shall receive from the Holders of at
least a majority of the Registrable Securities a written request or requests
that PMC effect a registration on Form S-3 and any related qualification or
compliance with respect to all or a part of the Registrable Securities owned by
such Holder or Holders, PMC shall:

          (a) promptly give written notice of the proposed registration, and any
     related qualification or compliance, to all other Holders; and

          (b) use best efforts to effect, as soon as practicable, such
     registration and all such qualifications and compliances as may be so
     requested and as would permit or facilitate the sale and distribution of
     all or such portion of such Holders' Registrable Securities as are
     specified in such request, together with all or such portion of the
     Registrable Securities of any other Holders joining in such request as are
     specified in a written request given within fifteen (15) days after receipt
     of such written notice from PMC, provided, however, that PMC shall not be
     obligated to effect any such registration, qualification or compliance,
     pursuant to this Section 1.4:

               (i) if Form S-3 is not available for such offering by the
          Holders;

               (ii) if the Holders, together with the holders of any other
          securities of PMC entitled to inclusion in such registration, propose
          to sell Registrable Securities and such other securities (if any) at
          an aggregate price to the public (net of any underwriters' discounts
          or commissions) of less than $500,000;

               (iii) if PMC shall furnish to the Holders a certificate signed by
          the Chief Executive Officer or Chairman of the Board of PMC stating
          that in the good faith judgment of the Board of Directors of PMC, it
          would be seriously detrimental to PMC and its stockholders for such
          Form S-3 Registration to be effected at such time, in which event PMC
          shall have the right to defer the filing of the Form S-3 registration
          statement for a period of not more than ninety (90) days after receipt
          of the request of the Holder or Holders under this Section 1.4;

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          provided, however, that PMC shall not utilize this right more than
          once in any twelve month period;

               (iv) if PMC has, within the twelve (12) month period preceding
          the date of such request, already effected two registrations on Form
          S-3 for the Holders pursuant to this Section 1.4; or

               (v) in any particular jurisdiction in which PMC would be required
          to qualify to do business or to execute a general consent to service
          of process in effecting such registration, qualification or
          compliance.

          (c) Subject to the foregoing, PMC shall file a registration statement
     covering the Registrable Securities and other securities so requested to be
     registered as soon as practicable after receipt of the request or requests
     of the Holders. Registrations effected pursuant to this Section 1.4 shall
     not be counted as requests for registration effected pursuant to Sections
     1.2.

     1.5 Obligations of PMC. Whenever required under this Section 1 to effect
the registration of any Registrable Securities, PMC shall, as expeditiously as
reasonably possible:

          (a) prepare and file with the SEC a registration statement with
     respect to such Registrable Securities and use best efforts to cause such
     registration statement to become effective, and, upon the request of the
     Holders of a majority of the Registrable Securities registered thereunder,
     keep such registration statement effective for a period of up to one
     hundred eighty (180) days or, if earlier, until the distribution
     contemplated in the Registration Statement has been completed;

          (b) prepare and file with the SEC such amendments and supplements to
     such registration statement and the prospectus used in connection with such
     registration statement as may be necessary to comply with the provisions of
     the Act with respect to the disposition of all securities covered by such
     registration statement;

          (c) furnish to the Holders such numbers of copies of a prospectus,
     including a preliminary prospectus, in conformity with the requirements of
     the Act, and such other documents as they may reasonably request in order
     to facilitate the disposition of Registrable Securities owned by them;

          (d) use best efforts to register and qualify the securities covered by
     such registration statement under such other securities or Blue Sky laws of
     such jurisdictions as shall be reasonably requested by the Holders,
     provided that PMC shall not be required in connection therewith or as a
     condition thereto to qualify to do business or to file a general consent to
     service of process in any such states or jurisdictions;

          (e) in the event of any underwritten public offering, enter into and
     perform its obligations under an underwriting agreement, in usual and
     customary form, with the managing underwriter of such offering;

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          (f) notify each Holder of Registrable Securities covered by such
     registration statement at any time when a prospectus relating thereto is
     required to be delivered under the Act or the happening of any event as a
     result of which the prospectus included in such registration statement, as
     then in effect, includes an untrue statement of a material fact or omits to
     state a material fact required to be stated therein or necessary to make
     the statements therein not misleading in the light of the circumstances
     then existing;

          (g) cause all such Registrable Securities registered pursuant
     hereunder to be listed on each securities exchange on which similar
     securities issued by PMC are then listed; and

          (h) provide a transfer agent and registrar for all Registrable
     Securities registered pursuant hereunder and a CUSIP number for all such
     Registrable Securities, in each case not later than the effective date of
     such registration.

     1.6 Information from Holder. It shall be a condition precedent to the
obligations of PMC to take any action pursuant to this Section 1 with respect to
the Registrable Securities of any selling Holder that such Holder shall furnish
to PMC such information regarding itself, the Registrable Securities held by it,
and the intended method of disposition of such securities as shall be required
to effect the registration of such Holder's Registrable Securities.

     1.7 Expenses of Registration. All expenses other than underwriting
discounts and commissions incurred in connection with registrations, filings or
qualifications pursuant to Sections 1.2, 1.3 and 1.4, including (without
limitation) all registration, filing and qualification fees, printers' and
accounting fees, fees and disbursements of counsel for PMC and the reasonable
fees and disbursements of one counsel for the selling Holders shall be borne by
PMC. Notwithstanding the foregoing, PMC shall not be required to pay for any
expenses of any registration proceeding begun pursuant to Section 1.2 or Section
1.4 if the registration request is subsequently withdrawn at the request of the
Holders of two-thirds of the Registrable Securities to be registered (in which
case all participating Holders shall bear such expenses pro rata based upon the
number of Registrable Securities that were to be requested in the withdrawn
registration), unless, in the case of a registration requested under Section
1.2, the Holders of a majority of the Registrable Securities agree to forfeit
their right to one demand registration pursuant to Section 1.2, provided,
however, that if at the time of such withdrawal, the Holders have learned of a
material adverse change in the condition, business, or prospects of PMC from
that known to the Holders at the time of their request and have withdrawn the
request with reasonable promptness following disclosure by PMC of such material
adverse change, then the Holders shall not be required to pay any of such
expenses and shall retain their rights pursuant to Section 1.2 or 1.4.

     1.8 Delay of Registration. No Holder shall have any right to obtain or seek
an injunction restraining or otherwise delaying any such registration as the
result of any controversy that might arise with respect to the interpretation or
implementation of this Section 1.

     1.9 Indemnification. In the event any Registrable Securities are included
in a registration statement under this Section 1:

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          (a) To the extent permitted by law, PMC will indemnify and hold
     harmless each Holder, the partners or officers, directors and stockholders
     of each Holder, legal counsel and accountants for each Holder, any
     underwriter (as defined in the Act) for such Holder and each person, if
     any, who controls such Holder or underwriter within the meaning of the Act
     or the 1934 Act, against any losses, claims, damages or liabilities (joint
     or several) to which they may become subject under the Act, the 1934 Act or
     any state securities laws, insofar as such losses, claims, damages, or
     liabilities (or actions in respect thereof) arise out of or are based upon
     any of the following statements, omissions or violations (collectively a
     "Violation"): (i) any untrue statement or alleged untrue statement of a
     material fact contained in such registration statement, including any
     preliminary prospectus or final prospectus contained therein or any
     amendments or supplements thereto, (ii) the omission or alleged omission to
     state therein a material fact required to be stated therein, or necessary
     to make the statements therein not misleading, or (iii) any violation or
     alleged violation by PMC of the Act, the 1934 Act, any state securities
     laws or any rule or regulation promulgated under the Act, the 1934 Act or
     any state securities laws; and PMC will reimburse each such Holder,
     underwriter or controlling person for any legal or other expenses
     reasonably incurred by them in connection with investigating or defending
     any such loss, claim, damage, liability or action; provided, however, that
     the indemnity agreement contained in this subsection 1.9(a) shall not apply
     to amounts paid in settlement of any such loss, claim, damage, liability or
     action if such settlement is effected without the consent of PMC (which
     consent shall not be unreasonably withheld), nor shall PMC be liable in any
     such case for any such loss, claim, damage, liability or action to the
     extent that it arises out of or is based upon a Violation that occurs in
     reliance upon and in conformity with written information furnished
     expressly for use in connection with such registration by any such Holder,
     underwriter or controlling person; provided further, however, that the
     foregoing indemnity agreement with respect to any preliminary prospectus
     shall not inure to the benefit of any Holder or underwriter, or any person
     controlling such Holder or underwriter, from whom the person asserting any
     such losses, claims, damages or liabilities purchased shares in the
     offering, if a copy of the prospectus (as then amended or supplemented if
     PMC shall have furnished any amendments or supplements thereto) was not
     sent or given by or on behalf of such Holder or underwriter to such person,
     if required by law so to have been delivered, at or prior to the written
     confirmation of the sale of the shares to such person, and if the
     prospectus (as so amended or supplemented) would have cured the defect
     giving rise to such loss, claim, damage or liability.

          (b) To the extent permitted by law, each selling Holder will indemnify
     and hold harmless PMC, each of its directors, each of its officers who has
     signed the registration statement, each person, if any, who controls PMC
     within the meaning of the Act, legal counsel and accountants for PMC, any
     underwriter, any other Holder selling securities in such registration
     statement and any controlling person of any such underwriter or other
     Holder, against any losses, claims, damages or liabilities (joint or
     several) to which any of the foregoing persons may become subject, under
     the Act, the 1934 Act or any state securities laws, insofar as such losses,
     claims, damages or liabilities (or actions in respect thereto) arise out of
     or are based upon any Violation, in each case to the extent (and only to
     the extent) that such Violation occurs in reliance upon and in conformity
     with written information furnished by such Holder expressly for use in

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     connection with such registration; and each such Holder will reimburse any
     person intended to be indemnified pursuant to this subsection 1.9(b), for
     any legal or other expenses reasonably incurred by such person in
     connection with investigating or defending any such loss, claim, damage,
     liability or action; provided, however, that the indemnity agreement
     contained in this subsection 1.9(b) shall not apply to amounts paid in
     settlement of any such loss, claim, damage, liability or action if such
     settlement is effected without the consent of the Holder (which consent
     shall not be unreasonably withheld), provided that in no event shall any
     indemnity under this subsection 1.9(b) exceed the gross proceeds from the
     offering received by such Holder.

          (c) Promptly after receipt by an indemnified party under this Section
     1.9 of notice of the commencement of any action (including any governmental
     action), such indemnified party will, if a claim in respect thereof is to
     be made against any indemnifying party under this Section 1.9, deliver to
     the indemnifying party a written notice of the commencement thereof and the
     indemnifying party shall have the right to participate in, and, to the
     extent the indemnifying party so desires, jointly with any other
     indemnifying party similarly noticed, to assume the defense thereof with
     counsel mutually satisfactory to the parties; provided, however, that an
     indemnified party (together with all other indemnified parties that may be
     represented without conflict by one counsel) shall have the right to retain
     one separate counsel, with the fees and expenses to be paid by the
     indemnifying party, if representation of such indemnified party by the
     counsel retained by the indemnifying party would be inappropriate due to
     actual or potential differing interests between such indemnified party and
     any other party represented by such counsel in such proceeding. The failure
     to deliver written notice to the indemnifying party within a reasonable
     time of the commencement of any such action, if prejudicial to its ability
     to defend such action, shall relieve such indemnifying party of any
     liability to the indemnified party under this Section 1.9, but the omission
     so to deliver written notice to the indemnifying party will not relieve it
     of any liability that it may have to any indemnified party otherwise than
     under this Section 1.9.

          (d) If the indemnification provided for in this Section 1.9 is held by
     a court of competent jurisdiction to be unavailable to an indemnified party
     with respect to any loss, liability, claim, damage or expense referred to
     herein, then the indemnifying party, in lieu of indemnifying such
     indemnified party hereunder, shall contribute to the amount paid or payable
     by such indemnified party as a result of such loss, liability, claim,
     damage or expense in such proportion as is appropriate to reflect the
     relative fault of the indemnifying party on the one hand and of the
     indemnified party on the other in connection with the statements or
     omissions that resulted in such loss, liability, claim, damage or expense,
     as well as any other relevant equitable considerations. The relative fault
     of the indemnifying party and of the indemnified party shall be determined
     by reference to, among other things, whether the untrue or alleged untrue
     statement of a material fact or the omission to state a material fact
     relates to information supplied by the indemnifying party or by the
     indemnified party and the parties' relative intent, knowledge, access to
     information, and opportunity to correct or prevent such statement or
     omission.

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          (e) Notwithstanding the foregoing, to the extent that the provisions
     on indemnification and contribution contained in the underwriting agreement
     entered into in connection with the underwritten public offering are in
     conflict with the foregoing provisions, the provisions in the underwriting
     agreement shall control.

          (f) The obligations of PMC and Holders under this Section 1.9 shall
     survive the completion of any offering of Registrable Securities in a
     registration statement under this Section 1, and otherwise.

     1.10 Reports Under Securities Exchange Act of 1934. With a view to making
available to the Holders the benefits of Rule 144 promulgated under the Act and
any other rule or regulation of the SEC that may at any time permit a Holder to
sell securities of PMC to the public without registration or pursuant to a
registration on Form S-3, PMC agrees to:

          (a) make and keep public information available, as those terms are
     understood and defined in SEC Rule 144, at all times after the effective
     date of the Initial Offering;

          (b) file with the SEC in a timely manner all reports and other
     documents required of PMC under the Act and the 1934 Act; and

          (c) furnish to any Holder, so long as the Holder owns any Registrable
     Securities, forthwith upon request (i) a written statement by PMC that it
     has complied with the reporting requirements of SEC Rule 144 (at any time
     after ninety (90) days after the effective date of the first registration
     statement filed by PMC), the Act and the 1934 Act (at any time after it has
     become subject to such reporting requirements), or that it qualifies as a
     registrant whose securities may be resold pursuant to Form S-3 (at any time
     after it so qualifies), (ii) a copy of the most recent annual or quarterly
     report of PMC and such other reports and documents so filed by PMC, and
     (iii) such other information as may be reasonably requested in availing any
     Holder of any rule or regulation of the SEC that permits the selling of any
     such securities without registration or pursuant to such form.

     1.11 Assignment of Registration Rights. The rights to cause PMC to register
Registrable Securities pursuant to this Section 1 may be assigned (but only with
all related obligations) by a Holder to a transferee or assignee of such
securities that (i) is a subsidiary, parent, partner, limited partner, retired
partner or stockholder of a Holder, (ii) is a Holder's family member or trust
for the benefit of an individual Holder, or (iii) after such assignment or
transfer, holds at least 25,000 shares of Registrable Securities (subject to
appropriate adjustment for stock splits, stock dividends, combinations and other
recapitalizations), provided: (a) PMC is, within a reasonable time after such
transfer, furnished with written notice of the name and address of such
transferee or assignee and the securities with respect to which such
registration rights are being assigned; (b) such transferee or assignee agrees
in writing to be bound by and subject to the terms and conditions of this
Agreement, including without limitation the provisions of Section 1.13 below;
and (c) such assignment shall be effective only if immediately following such
transfer the further disposition of such securities by the transferee or
assignee is restricted under the Act.

                                       10

<PAGE>

     1.12 Limitations on Subsequent Registration Rights. From and after the date
of this Agreement, PMC shall not, without the prior written consent of either
APS Financial or the Holders of two-thirds of the Registrable Securities, enter
into any agreement with any holder or prospective holder of any securities of
PMC that would allow such holder or prospective holder (a) to include such
securities in any registration filed under Section 1.3 hereof, unless under the
terms of such agreement, such holder or prospective holder may include such
securities in any such registration only to the extent that the inclusion of
such securities will not reduce the amount of the Registrable Securities of the
Holders that are included or (b) to demand registration of their securities.

     1.13 "Market Stand-Off" Agreement. Each Holder hereby agrees that it will
not, without the prior written consent of the managing underwriter, during the
period commencing on the date of the final prospectus relating to PMC's initial
public offering and ending on the date specified by PMC and the managing
underwriter (such period not to exceed one hundred eighty (180) days) (i) lend,
offer, pledge, sell, contract to sell, sell any option or contract to purchase,
purchase any option or contract to sell, grant any option, right or warrant to
purchase, or otherwise transfer or dispose of, directly or indirectly, any
shares of Common Stock or any securities convertible into or exercisable or
exchangeable for Common Stock (whether such shares or any such securities are
then owned by the Holder or are thereafter acquired), or (ii) enter into any
swap or other arrangement that transfers to another, in whole or in part, any of
the economic consequences of ownership of the Common Stock, whether any such
transaction described in clause (i) or (ii) above is to be settled by delivery
of Common Stock or such other securities, in cash or otherwise. The foregoing
provisions of this Section 1.13 shall apply only to PMC's initial public
offering of equity securities, shall not apply to the sale of any shares to an
underwriter pursuant to an underwriting agreement, and shall only be applicable
to the Holders if all officers and directors and greater than five percent (5%)
stockholders of PMC enter into similar agreements. The underwriters in
connection with PMC's initial public offering are intended third party
beneficiaries of this Section 1.13 and shall have the right, power and authority
to enforce the provisions hereof as though they were a party hereto.

     In order to enforce the foregoing covenant, PMC may impose stop-transfer
instructions with respect to the Registrable Securities of each Holder (and the
shares or securities of every other person subject to the foregoing restriction)
until the end of such period.

     1.14 Termination of Registration Rights. No Holder shall be entitled to
exercise any right provided for in this Section 1 after five (5) years following
the consummation of the Initial Offering or, as to any Holder, such earlier time
at which all Registrable Securities held by such Holder (and any affiliate of
the Holder with whom such Holder must aggregate its sales under Rule 144) can be
sold in any three (3)-month period without registration in compliance with Rule
144 of the Act.

     2.   Miscellaneous.

     2.1 Successors and Assigns. Except as otherwise provided herein, the terms
and conditions of this Agreement shall inure to the benefit of and be binding
upon the respective successors and assigns of the parties (including transferees
of any shares of Registrable Securities). Nothing in this Agreement, express or
implied, is intended to confer upon any party

                                       11

<PAGE>

other than the parties hereto or their respective successors and assigns any
rights, remedies, obligations, or liabilities under or by reason of this
Agreement, except as expressly provided in this Agreement.

     2.2 Governing Law. This Agreement shall be governed by and construed under
the laws of the State of Texas as applied to agreements among Texas residents
entered into and to be performed entirely within Texas.

     2.3 Counterparts. This Agreement may be executed in two or more
counterparts, each of which shall be deemed an original, but all of which
together shall constitute one and the same instrument.

     2.4 Titles and Subtitles. The titles and subtitles used in this Agreement
are used for convenience only and are not to be considered in construing or
interpreting this Agreement.

     2.5 Notices. Unless, otherwise provided, any notice required or permitted
under this Agreement shall be given in writing and shall be deemed effectively
given upon personal delivery to the party to be notified or upon delivery by
confirmed facsimile transmission, nationally recognized overnight courier
service, or upon deposit with the United States Post Office, by registered or
certified mail, postage prepaid and addressed to the party to be notified at the
address indicated for such party on the signature page hereof, or at such other
address as such party may designate by ten (10) days' advance written notice to
the other parties.

     2.6 Expenses. If any action at law or in equity is necessary to enforce or
interpret the terms of this Agreement, the prevailing party shall be entitled to
reasonable attorneys' fees, costs and necessary disbursements in addition to any
other relief to which such party may be entitled.

     2.7 Entire Agreement: Amendments and Waivers. This Agreement (including the
Exhibits hereto, if any) constitutes the full and entire understanding and
agreement among the parties with regard to the subjects hereof and thereof. Any
term of this Agreement may be amended and the observance of any term of this
Agreement may be waived (either generally or in a particular instance and either
retroactively or prospectively), only with the written consent of PMC and the
holders of two-thirds of the Registrable Securities. Any amendment or waiver
effected in accordance with this paragraph shall be binding upon each holder of
any Registrable Securities, each future holder of all such Registrable
Securities, and PMC.

     2.8 Severability. If one or more provisions of this Agreement are held to
be unenforceable under applicable law, such provision shall be excluded from
this Agreement and the balance of the Agreement shall be interpreted as if such
provision were so excluded and shall be enforceable in accordance with its
terms.

     2.9 Aggregation of Stock. All shares of Registrable Securities held or
acquired by affiliated entities or persons shall be aggregated together for the
purpose of determining the availability of any rights under this Agreement.

                            [Signature Pages Follow]

                                       12

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               POLAR MOLECULAR CORPORATON


                                               By: /s/ Mark L. Nelson
                                                   -----------------------------
                                                       Mark L. Nelson, President

                                      S-1

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               INVESTOR

                                               CAMBRIDGE STRATEGIES GROUP, LLC


                                               By: /s/
                                                   -----------------------------
                                               Printed Name:
                                                             -------------------
                                               Title:
                                                      --------------------------

                                      S-2

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               INVESTOR


                                               /s/ E. Bruce McClendon, M.D.
                                               ---------------------------------
                                                   E. Bruce McClendon, M.D.

                                      S-3

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               INVESTOR


                                               /s/ Peter K. Aman
                                               ---------------------------------
                                                   Peter K. Aman

                                      S-4

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               INVESTOR

                                               BISCHOFF FAMILY PARTNERS


                                               By: /s/
                                                   -----------------------------
                                               Printed Name:
                                                             -------------------
                                               Title:
                                                      --------------------------

                                      S-5

<PAGE>

     IN WITNESS WHEREOF, the parties have executed this Agreement as of the date
first above written.

                                               INVESTOR


                                               /s/ C. Don Van Wart
                                               ---------------------------------
                                                   C. Don Van Wart

                                      S-6