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                                                                    EXHIBIT 10.2


                           THIRD AMENDED AND RESTATED

                             SHAREHOLDERS AGREEMENT

                                  BY AND AMONG

                         WESTPORT RESOURCES CORPORATION
                              ERI INVESTMENTS, INC.
                               WESTPORT ENERGY LLC
                               MEDICOR FOUNDATION

                                       AND

                        CERTAIN STOCKHOLDERS NAMED HEREIN


                          DATED AS OF FEBRUARY 14, 2003

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                                TABLE OF CONTENTS

                                                                            PAGE


ARTICLE I DEFINITIONS .........................................................2

     Section 1.1.  Definitions ................................................2


ARTICLE II REPRESENTATIONS AND WARRANTIES .....................................7

     Section 2.1. Representations and Warranties of the Company ...............7
     Section 2.2. Representations and Warranties of Medicor ...................7
     Section 2.3. Representations and Warranties of ERI .......................7
     Section 2.4. Representations and Warranties of the Belfer Group ..........8


ARTICLE III CORPORATE GOVERNANCE; CERTAIN CORPORATE ACTIONS ...................9

     Section 3.1. Voting of Shares ............................................9
     Section 3.2. Composition of the Board of Directors .......................9
     Section 3.3. Approval of Major Actions ..................................11
     Section 3.4. Amendments to Articles of Incorporation and Bylaws .........11
     Section 3.5. Self-Interested Transactions ...............................11


ARTICLE IV STANDSTILL ........................................................12

     Section 4.1. Standstill .................................................12


ARTICLE V REGISTRATION RIGHTS ................................................13

     Section 5.1. Demand Registrations .......................................13
     Section 5.2  Piggyback Registrations ....................................15
     Section 5.3. Holdback Agreements ........................................16
     Section 5.4. Registration Procedures ....................................17
     Section 5.5. Registration Expenses ......................................19
     Section 5.6. Indemnification ............................................20
     Section 5.7. Participation in Underwritten Registrations ................21
     Section 5.8. Current Public Information .................................22
     Section 5.9. Cooperation ................................................22


ARTICLE VI GENERAL PROVISIONS ................................................22

     Section 6.1. Notices ....................................................22
     Section 6.2. Assignment; Binding Effect; Benefit ........................25
     Section 6.3. Entire Agreement ...........................................25
     Section 6.4. Amendment ..................................................25


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    Section 6.5.  Governing Law; Jurisdiction ................................25
    Section 6.6.  Counterparts ...............................................25
    Section 6.7.  Headings ...................................................26
    Section 6.8.  Interpretation                                              26
    Section 6.9.  Incorporation of Exhibits and Schedules ....................26
    Section 6.10. Severability ...............................................26
    Section 6.11. Enforcement of Agreement ...................................26
    Section 6.12. Confidentiality ............................................26
    Section 6.13. Termination ................................................26
    Section 6.14. Belfer Group Representative ................................27
    Section 6.15. Medicor Group Representative ...............................27
    Section 6.16. Effective Time .............................................27


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                           THIRD AMENDED AND RESTATED
                             SHAREHOLDERS AGREEMENT

     This THIRD AMENDED AND RESTATED SHAREHOLDERS AGREEMENT, dated as of
February 14, 2003 (this "Agreement"), is entered into by and among Westport
Resources Corporation, a Nevada corporation ("Westport" or the "Company"),
Westport Energy LLC, a Delaware limited liability company ("WELLC"), ERI
Investments, Inc., a Delaware corporation ("ERI"), Medicor Foundation, a
Liechtenstein foundation, formed pursuant to the Liechtenstein Persons and
Companies Act ("Medicor," and together with WELLC, the "Medicor Group") and the
persons and entities named on Exhibit A (each such person or entity, a "Belfer
Person," and collectively, the "Belfer Group").

     WHEREAS, Westport Oil and Gas Company, Inc. ("WOGC"), Equitable Production
Company ("EPC"), Equitable Production (Gulf) Company ("EPGC"), Westport Energy
Corporation ("WEC") and EPGC Merger Sub Corporation ("Merger Sub") entered into
a Merger Agreement dated as of March 9, 2000 (the "EPGC Merger Agreement")
providing for the merger of Merger Sub with and into WOGC and for the conversion
of the WOGC capital stock held by WEC into shares of EPGC capital stock, such
that immediately after the merger, EPC owned approximately 49% of the capital
stock of EPGC and WEC owned approximately 51% of the capital stock of EPGC (the
"EPGC Merger"); and

     WHEREAS, as a condition to the consummation of the transactions
contemplated by the EPGC Merger Agreement, WEC, EPC and EPGC entered into that
certain Shareholders Agreement dated as of March 9, 2000 (the "Original
Shareholders Agreement"); and

     WHEREAS, subsequent to the EPGC Merger, EPC assigned its interest in EPGC
to ERI, WEC became WELLC by statutory conversion, and EPGC changed its name to
Westport Resources Corporation; and

     WHEREAS, Westport Resources Corporation, a Delaware corporation ("Old
Westport") and Belco Oil & Gas Corp., a Nevada corporation ("Belco") entered
into an Agreement and Plan of Merger dated as of June 8, 2001 (the "Merger
Agreement") providing for, among other things, the merger (the "Merger") of Old
Westport with and into Belco, with Belco as the surviving corporation, and for
the conversion of 100% of the issued and outstanding shares of Old Westport
Common Stock, par value $.01 per share ("Old Westport Common Stock") into Common
Stock (as hereinafter defined) and the automatic cancellation and retirement of
the Old Westport Common Stock; and

     WHEREAS, concurrently with the execution and delivery of the Merger
Agreement, Belco, Old Westport, WELLC, ERI and the Belfer Group (as then
comprised, the "Original Belfer Group") entered into an Amended and Restated
Shareholders Agreement (the "Amended Shareholders Agreement"), the purpose of
which was to amend and restate the Original Shareholders Agreement to reflect
the effects of the Merger by, among other things, (i) having it apply to the
shares of Common Stock issued to WELLC and ERI in connection with the Merger in
exchange for their Old Westport Common Stock and (ii) adding Belco and the
Original Belfer Group as parties; and


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     WHEREAS, Belco, Westport, WELLC, ERI and the Original Belfer Group entered
into a Second Amended and Restated Shareholders Agreement dated as of July 20,
2001 (the "Second Amended and Restated Shareholders Agreement") to effect
certain modifications to the Amended Shareholders Agreement; and

     WHEREAS, subsequent to the Merger, Belco changed its name to Westport
Resources Corporation; and

     WHEREAS, WELLC has transferred certain of its shares of Common Stock to
Medicor; and

     WHEREAS, certain Persons in the Original Belfer Group have made various
Transfers to Permitted Transferees, changing the composition of the Original
Belfer Group; and

     WHEREAS, the purpose of this Agreement is to effect certain modifications
relating to the transfer of Common Stock by WELLC to Medicor, certain Transfers
to Permitted Transferees made by Persons in the Original Belfer Group and to
amend and restate such Second Amended and Restated Shareholders Agreement, as so
modified, in its entirety;

     NOW, THEREFORE, in consideration of the foregoing, and of the
representations, warranties, covenants and agreements contained herein, and for
other good and valuable consideration, the receipt and sufficiency of which is
hereby acknowledged, the parties hereto, intending to be legally bound, hereby
agree as follows:

                                   ARTICLE I
                                   DEFINITIONS

     Section 1.1. Definitions.

     "Affiliate" shall have the meaning set forth in Rule 12b-2 of the
regulations promulgated under the Exchange Act.

     "Agreement" shall have the meaning set forth in the preamble to this
Agreement.

     "Amended Shareholders Agreement" shall have the meaning set forth in the
preamble to this Agreement.

     "Belco" shall have the meaning set forth in the preamble to this Agreement.

     "Belfer Group" shall have the meaning set forth in the preamble to this
Agreement.

     "Belfer Group Representative" shall have the meaning set forth in Section
6.14.

     "Belfer Parties" shall mean the Belfer Group and their Permitted
Transferees.

     "Belfer Person" shall mean any Person included in the Belfer Group.


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     "Board of Directors" shall mean the board of directors of the Company.

     "Commission" shall mean the Securities and Exchange Commission or any other
Federal agency at the time administering the Securities Act.

     "Common Stock" shall mean the common stock of the Company, par value $.01
per share, now or hereafter authorized to be issued.

     "Company" shall have the meaning set forth in the preamble to this
Agreement.

     "Consolidated Net Worth" shall mean, at any particular time, all amounts
which, in conformity with GAAP, would be included as common stockholders' equity
on a consolidated balance sheet of the Company and its Subsidiaries.

     "Debt" shall mean (a) Funded Debt, plus (b) at any particular time, all
amounts which, in conformity with GAAP, would be included as preferred
stockholders' equity on a consolidated balance sheet of the Company and its
Subsidiaries less (c) cash of the Company and its Subsidiaries.

     "Demand Registrations" shall have the meaning set forth in Section 5.l(a).

     "Director" shall mean a member of the Board of Directors.

     "Disinterested Director" shall have the meaning set forth in Section 3.5.

     "Effective Time" shall have the meaning set forth in Section 6.16.

     "EPC" shall have the meaning set forth in the preamble to this Agreement.

     "EPGC" shall have the meaning set forth in the preamble to this Agreement.

     "EPGC Merger" shall have the meaning set forth in the preamble to this
Agreement.

     "EPGC Merger Agreement" shall have the meaning set forth in the preamble to
this Agreement.

     "ERI" shall have the meaning set forth in the preamble to this Agreement.

     "ERI Parties" shall mean ERI and its Permitted Transferees.

     "Exchange Act" shall mean the Securities Exchange Act of 1934, as amended,
and the rules and regulations of the Commission thereunder, all as the same
shall be in effect at the time.

     "Funded Debt" shall mean at any time (without duplication): (a) all
obligations of the Company and its Subsidiaries, or any of them, for borrowed
money and all obligations of the Company and its Subsidiaries, or any of them,
evidenced by bonds, notes, debentures, or other


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similar instruments, (b) all capital lease obligations of the Company and its
Subsidiaries, or any of them, (c) all debt or other obligations of others
guaranteed by the Company and its Subsidiaries, or any of them to the extent of
such guarantee, (d) all reimbursement obligations of the Company and its
Subsidiaries, or any of them (whether contingent or otherwise) in respect of
letters of credit, bankers' acceptances, surety or other bonds and similar
instruments, (e) all obligations of the Company and its Subsidiaries, or any of
them, to pay the deferred purchase price of property or services, except trade
accounts payable of the Company and its Subsidiaries, or any of them, arising in
the ordinary course of business that are not past due by more than ninety (90)
days, (f) all obligations secured by a lien existing on property owned by the
Company and its Subsidiaries, or any of them, whether or not the obligations
secured thereby have been assumed by the Company and its Subsidiaries, or any of
them, or are non-recourse to the credit of the Company and its Subsidiaries, or
any of them, and (g) all other debt of the Company and its Subsidiaries, or any
of them.

     "GAAP" shall mean generally accepted accounting principles in the United
States.

     "Independent Director" shall mean an individual (i) who is not a director,
officer, employee or Affiliate of the Company, WELLC, Medicor, the Belfer Group
or ERI, or any of their respective Affiliates, (ii) who is not a former
director, officer or employee of the Company, Old Westport, WELLC, Medicor, the
Belfer Group or ERI, or any of their respective Affiliates, (iii) who has not
had and who is not a director, officer, 10% or more equity owner or Affiliate of
any Person that has had a direct or indirect interest in any transaction in the
preceding 24 months with the Company, Old Westport, WELLC, Medicor, the Belfer
Group or ERI, or any of their respective Affiliates, and (iv) who does not
represent the Company, WELLC, Medicor, the Belfer Group or ERI, or any of their
respective Affiliates, and any Independent Director appointed shall be required
to certify in writing to this effect upon request.

     "Major Actions" shall mean those actions described in Sections 3.3.

     "Medicor" shall have the meaning set forth in the preamble to this
Agreement.

     "Medicor Group" shall have the meaning set forth in the preamble to this
Agreement.

     "Medicor Group Representative" shall have the meaning set forth in Section
6.15.

     "Medicor Parties" shall mean the Medicor Group and their Permitted
Transferees.

     "Medicor Person" shall mean any Person included in the Medicor Group.

     "Merger" shall have the meaning set forth in the preamble to this
Agreement.

     "Merger Agreement" shall have the meaning set forth in the preamble to this
Agreement.

     "Merger Sub" shall have the meaning set forth in the preamble to this
Agreement.

     "Old Westport" shall have the meaning set forth in the preamble to this
Agreement.


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     "Old Westport Common Stock" shall have the meaning set forth in the
preamble to this Agreement.

     "Original Belfer Group" shall have the meaning set forth in the preamble to
this Agreement.

     "Original Shareholders Agreement" shall have the meaning set forth in the
preamble to this Agreement.

     "Party" or "Parties" shall mean ERI, the Medicor Group and/or the Belfer
Group.

     "Permitted Transferees" shall mean in the case of the Medicor Parties: (A)
a Medicor Person, any spouse, issue, parent or relatives of the Medicor Parties,
or (i) trusts for the benefit of any of such Persons, (ii) entities controlling
or controlled by any of such Persons and (iii) in the event of the death of any
such individual person, heirs or testamentary legatees of such person, in each
case to whom a Medicor Party has transferred its Shares and who has agreed in
writing to be bound by the terms of this Agreement, and (B) any Subsidiary or
Affiliate of the Medicor Group to which a Medicor Party has transferred its
Shares and which has agreed in writing to be bound by the terms of this
Agreement; in the case of the ERI Parties: (A) ERI, any spouse, issue, parent or
relatives of the ERI Parties, or (i) trusts for the benefit of any of such
Persons, (ii) entities controlling or controlled by any of such Persons and
(iii) in the event of the death of any such individual person, heirs or
testamentary legatees of such person, in each case to whom an ERI Party has
transferred its Shares and who has agreed in writing to be bound by the terms of
this Agreement, and (B) any Subsidiary or Affiliate of ERI to which an ERI Party
has transferred its Shares and which has agreed in writing to be bound by the
terms of this Agreement; and in the case of the Belfer Parties: a Belfer Person,
any spouse, issue, parent or relatives of the Belfer Parties, or (i) trusts for
the benefit of any of such Persons, (ii) entities controlling or controlled by
any of such Persons and (iii) in the event of the death of any such individual
person, heirs or testamentary legatees of such person, in each case to whom a
Belfer Party has transferred its Shares and who has agreed in writing to be
bound by the terms of this Agreement;

     "Person" shall mean any natural person, corporation, partnership, limited
liability company, firm, association, trust, government, governmental agency or
other entity, whether acting in an individual, fiduciary or other capacity.

     "Piggyback Registration" shall have the meaning set forth in Section
5.2(a).

     "Registrable Securities" shall mean (i) any shares of Common Stock owned
by, or otherwise hereafter acquired by, the Medicor Parties, the ERI Parties or
the Belfer Parties, and (ii) any securities issued as a dividend on or other
distribution with respect to or in exchange, replacement or in subdivision of,
any such Common Stock. As to any particular Registrable Securities, such
securities shall cease to be Registrable Securities when (A) a registration
statement (other than the Form S-4 pursuant to which the issuance of Common
Stock in connection with the Merger is registered under the Securities Act) with
respect to the sale of such securities shall have been declared effective under
the Securities Act and such securities shall have been disposed of in accordance
with such registration statement, or (B) such securities shall


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have been sold (other than in a privately negotiated sale) pursuant to Rule 144
(or any successor provision) under the Securities Act.

     "Registration Expenses" shall have the meaning set forth in Section 5.5(a).

     "Second Amended and Restated Shareholders Agreement" shall have the meaning
set forth in the preamble to this Agreement.

     "Securities Act" shall mean the Securities Act of 1933, as amended, and the
rules and regulations of the Commission thereunder, as the same shall be in
effect at the time.

     "Self-Interested Transaction" shall have the meaning set forth in Section
3.5.

     "Shares" shall mean shares of Common Stock.

     "Short-Form Registrations" shall have the meaning set forth in Section
5.l(a).

     "Subsidiary" of any Person shall mean any corporation or other legal entity
of which such Person (either alone or through or together with any other
Subsidiary) owns, directly or indirectly, 50% or more of the stock or other
equity interests, the holders of which are generally entitled to vote for the
election of the board of directors or other governing body of such corporation
or other legal entity.

     "Supermajority Approval" shall mean approval by action of at least a
majority of all of the members of the Board of Directors which shall include not
less than one less than all of the Directors whom the Parties then have the
right to nominate pursuant to Section 3.2.

     "Total Capitalization" shall mean the sum of (i) Consolidated Net Worth and
(ii) Debt.

     "Transfer" shall mean to sell, transfer, assign, pledge or otherwise
dispose.

     "Underwriter" shall mean nationally recognized investment banking firm with
experience serving as lead managing underwriter for public offerings of the
stock of companies engaged in the exploration, development and production of oil
and natural gas.

     "WEC" shall have the meaning set forth in the preamble to this Agreement.

     "WELLC" shall have the meaning set forth in the preamble to this Agreement.

     "Westport" shall have the meaning set forth in the preamble to this
Agreement.

     "WOGC" shall have the meaning set forth in the preamble to this Agreement.


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                                   ARTICLE II
                         REPRESENTATIONS AND WARRANTIES

     Section 2.1. Representations and Warranties of the Company. The Company
hereby represents and warrants to the other Parties hereto as follows: The
Company has all requisite corporate power and authority to enter into this
Agreement and to consummate the transactions contemplated hereby. The execution
and delivery by the Company of this Agreement, and the consummation by the
Company of the transactions contemplated hereby, have been duly authorized by
all necessary corporate action on the part of the Company. This Agreement has
been duly executed and delivered by the Company and constitutes a valid and
binding obligation of the Company enforceable against the Company in accordance
with its terms. No consent, approval, order or authorization of, or
registration, declaration or filing with, any court, administrative agency or
commission or other governmental authority or instrumentality, domestic or
foreign, is required by, or with respect to, the Company in connection with the
execution and delivery of this Agreement by the Company or the consummation by
the Company of the transactions contemplated hereby. The execution and delivery
of this Agreement by the Company and the consummation of the transactions
contemplated hereby by the Company does not conflict with, or result in a breach
of, any law or regulation of any governmental authority applicable to the
Company or any material agreement to which the Company is a party.

     Section 2.2. Representations and Warranties of Medicor. Each Medicor Person
hereby severally and not jointly represents and warrants to the other Parties
hereto as follows:

          (a) Authority. Each Medicor Person has all requisite corporate or
other power and authority to enter into this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery by such Medicor
Person of this Agreement, and the consummation by such Medicor Person of the
transactions contemplated hereby, have been duly authorized by all necessary
corporate or other action on the part of such Medicor Person. This Agreement has
been duly executed and delivered by such Medicor Person and constitutes a valid
and binding obligation of such Medicor Person enforceable against such Medicor
Person in accordance with its terms. No consent, approval, order or
authorization of, or registration, declaration or filing with, any court,
administrative agency or commission or other governmental authority or
instrumentality, domestic or foreign, is required by, or with respect to, such
Medicor Person in connection with the execution and delivery of this Agreement
by such Medicor Person or the consummation by such Medicor Person of the
transactions contemplated hereby. The execution and delivery of this Agreement
by such Medicor Person and the consummation by such Medicor Person of the
transactions contemplated hereby by it do not conflict with, or result in a
breach of, any law or regulation of any governmental authority applicable to
such Medicor Person or any material agreement to which such Medicor Person is a
party.

          (b) Shares. Schedule 2.2 sets forth the ownership of the Shares held
by each Medicor Person as of the date hereof.

     Section 2.3. Representations and Warranties of ERI. ERI hereby represents
and warrants to the other Parties hereto as follows:


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          (a) Authority. Each of the ERI Parties has all requisite corporate or
other power and authority to enter into this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery by the ERI Parties
of this Agreement and the consummation by the ERI Parties of the transactions
contemplated hereby have been duly authorized by all necessary corporate or
other action on the part of each of the ERI Parties. This Agreement has been
duly executed and delivered by each of the ERI Parties and constitutes a valid
and binding obligation of each of the ERI Parties enforceable against each of
the ERI Parties in accordance with its terms. No consent, approval, order or
authorization of, or registration, declaration or filing with, any court,
administrative agency or commission or other governmental authority or
instrumentality, domestic or foreign, is required by, or with respect to, any of
the ERI Parties in connection with the execution and delivery of this Agreement
by the ERI Parties or the consummation by each of the ERI Parties of the
transactions contemplated hereby. The execution and delivery by the ERI Parties
of this Agreement and the consummation by the ERI Parties of the transactions
contemplated hereby do not conflict with, or result in a breach of, any law or
regulation of any governmental authority applicable to any of the ERI Parties or
any material agreement to which any of the ERI Parties is a party.

          (b) Shares. Schedule 2.3 sets forth the ownership of the Shares held
by the ERI Parties as of the date hereof.

     Section 2.4. Representations and Warranties of the Belfer Group. Each
Belfer Person hereby severally and not jointly represents and warrants to the
other Parties hereto as follows:

          (a) Authority. Such Belfer Person has all requisite corporate or other
power and authority to enter into this Agreement and to consummate the
transactions contemplated hereby. The execution and delivery by such Belfer
Person of this Agreement, and the consummation by such Belfer Person of the
transactions contemplated hereby, have been duly authorized by all necessary
corporate or other action on the part of such Belfer Person. This Agreement has
been duly executed and delivered by such Belfer Person and constitutes a valid
and binding obligation of such Belfer Person enforceable against such Belfer
Person in accordance with its terms. No consent, approval, order or
authorization of, or registration, declaration or filing with, any court,
administrative agency or commission or other governmental authority or
instrumentality, domestic or foreign, is required by, or with respect to, such
Belfer Person in connection with the execution and delivery of this Agreement by
such Belfer Person or the consummation by such Belfer Person of the transactions
contemplated hereby. The execution and delivery of this Agreement by such Belfer
Person and the consummation by such Belfer Person of the transactions
contemplated hereby by it do not conflict with, or result in a breach of, any
law or regulation of any governmental authority applicable to such Belfer Person
or any material agreement to which such Belfer Person is a party.

          (b) Shares. Schedule 2.4 sets forth the ownership of the Shares held
by each Belfer Person as of the date hereof.


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                                   ARTICLE III
                 CORPORATE GOVERNANCE; CERTAIN CORPORATE ACTIONS

     Section 3.1. Voting of Shares.

          (a) The Medicor Parties shall vote all shares of Common Stock owned or
controlled by them, and shall take all other necessary or desirable actions
within their control (including, without limitation, attendance at meetings in
person or by proxy for purposes of obtaining a quorum and execution of written
consents in lieu of meetings), to effectuate the provisions of this Agreement.

          (b) The ERI Parties shall vote all shares of Common Stock owned or
controlled by them, and shall take all other necessary or desirable action
within their control (including, without limitation, attendance at meetings in
person or by proxy for purposes of obtaining a quorum and execution of written
consents in lieu of meetings), to effectuate the provisions of this Agreement.

          (c) The Belfer Parties shall vote all shares of Common Stock owned or
controlled by them, and shall take all other necessary or desirable action
within their control (including, without limitation, attendance at meetings in
person or by proxy for purposes of obtaining a quorum and execution of written
consents in lieu of meetings), to effectuate the provisions of this Agreement.

          (d) The Company shall take all necessary or desirable actions within
its control (including, without limitation, calling special board and
stockholder meetings) to effectuate the provisions of this Agreement.

     Section 3.2. Composition of the Board of Directors. (i) The Medicor Parties
shall vote all shares of Common Stock owned or controlled by them, and shall
take all necessary action within their control, (ii) the ERI Parties shall vote
all shares of Common Stock owned or controlled by them, and shall take all
necessary actions within their control and (iii) the Belfer Parties shall vote
all shares of Common Stock owned or controlled by them, and shall take all
necessary action within their control, in each case, so that the composition of
the Board of Directors and the manner of selecting members thereof shall be as
follows:

          (a) The Board of Directors shall be comprised of eleven (11) Directors
(two of whom shall be Independent Directors) divided into three classes, with
Directors in each class having a three-year term following a transition period
in which the initial Class 1 Directors serve a one-year term, the initial Class
2 Directors serve a two-year term and the initial Class 3 Directors serve a
three-year term. Medicor and ERI shall each have the right to nominate one (1)
Director to Class 3, one (1) Director to Class 2 and one (1) Director to Class 1
and the Belfer Group shall have the right to nominate one (1) Director to Class
3 and one (1) Director to Class 1; provided, that the existing membership of the
Board of Directors and the class to which each director nominee belongs shall
not be affected by the execution of this Agreement. Each of Medicor, ERI and the
Belfer Group, respectively, shall have the right: (i) subject to applicable law,
including Nevada Revised Statutes 78.335(1) requiring a vote of not less than
two-thirds of the issued and outstanding voting power to remove an incumbent
director, to remove, with or


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without cause, any Director nominated in accordance with this Section 3.2 by
Medicor, ERI or the Belfer Group, respectively, and each of the Medicor Parties,
the ERI Parties and the Belfer Parties shall vote their Shares in furtherance of
this provision; and (ii) to nominate any replacement for a Director nominated in
accordance with this Section 3.2 by Medicor, ERI or the Belfer Group,
respectively, upon the death, resignation, retirement, disqualification or
removal from office of such Director. The Board of Directors shall duly appoint
as a Director each person so nominated to fill a vacancy on the Board of
Directors. Notwithstanding the foregoing:

               (i) if either the Medicor Parties or the ERI Parties own less
than 18% of the Company's then outstanding Common Stock, then Medicor or ERI, as
the case may be, shall have the right to nominate only: (x) one (1) Director to
the class of Directors having the then longest remaining term; and (y) one (1)
Director to the class of Directors having the next longest remaining term;
provided that in either case, if necessary to put one or more of a Party's
Director nominees into such classes, the Company and the other Parties shall
cooperate as necessary to effect such nomination; provided, further, that the
right to change such classes may only be exercised in connection with the
reduction in the number of the Party's Director nominees;

               (ii) if either the Medicor Parties, the ERI Parties or the Belfer
Parties own less than 8% of the Company's then outstanding Common Stock, then
Medicor, ERI or the Belfer Group, as the case may be, shall have the right to
nominate only one (1) Director to the class of Directors having the then longest
remaining term; provided that if necessary to put a Party's Director nominee
into such class, the Company and the other Parties shall cooperate as necessary
to effect such nomination; provided, further, that the right to change such
classes may only be exercised in connection with the reduction in the number of
the Party's Director nominees; and

               (iii) if either the Medicor Parties, the ERI Parties or the
Belfer Parties own less than 5% of the Company's then outstanding Common Stock,
then Medicor, ERI or the Belfer Group, as the case may be, shall not have the
right to nominate any Directors.

          (b) For so long as any Party has the right to nominate a Director
under this Agreement, the Company will give such Party written notice of each
regularly scheduled meeting of its Board of Directors as far in advance as such
notice is required to be delivered to the Directors (and at least three business
days prior to the date of each special meeting of the Board of Directors), and
the Board of Directors will permit up to two (2) representatives of each such
Party to attend as observers of all meetings of the Board of Directors
(including any meetings of committees thereof); provided that in the case of
telephonic meetings conducted in accordance with the Company's bylaws and
applicable law, each such Party's representatives will be given the opportunity
to listen to such telephonic meetings. Each representative will be entitled to
receive all written materials and other information (including, without
limitation, copies of meeting minutes and press releases) given to Directors in
connection with such meetings at the same time such materials and information
are given to the Directors. If the Board of Directors proposes to take any
action by written consent in lieu of a meeting of the Board of Directors or of
any committee thereof, the Company will give written notice thereof to each such
Party who has the right to nominate a director under this Agreement prior to the
effective date of such consent describing in reasonable detail the nature and
substance of such


                                      -10-
<PAGE>


action. The Company will reimburse each Party that has observer rights under
this Section 3.2(b) for all reasonable expenses incurred by such Party's
representatives in connection with attending meetings of the Board of Directors
and committees thereof.

     Section 3.3. Approval of Major Actions. The Company may take and may permit
its Subsidiaries to take and engage in the following Major Actions only upon
receiving Supermajority Approval:

          (a) Issuance of Capital Stock. Any issuance, sale, grant or award or
entering into any agreement to issue, sell, grant or award any capital stock of
the Company other than (i) pursuant to agreements or obligations in existence
prior to the date hereof and permitted under the terms of the Second Amended and
Restated Shareholders Agreement, (ii) the issuance of capital stock of the
Company pursuant to any rights or agreements including without limitation any
security convertible or exchangeable into or exercisable for, with or without
consideration, capital stock of the Company so long as such rights or agreements
received Supermajority Approval and (iii) the grant of options and the issuance
of restricted stock under Company stock incentive plans for the benefit of the
Company's employees and directors and the issuance of Common Stock upon the
exercise of such options.

          (b) Debt to Total Capitalization. Incur Funded Debt of the Company and
its Subsidiaries so that the ratio of Debt of the Company and its Subsidiaries
to Total Capitalization is greater than 0.4 to 1.0.

          (c) Sale Transactions. Any merger or consolidation of the Company, the
sale of all or substantially all of the assets of the Company or the sale of
assets or transfer to a third party by sale of assets, merger or otherwise by
the Company or any of its Subsidiaries (in one transaction or a series of
related transactions) of any Subsidiary of the Company or the assets or business
of the Company or a Subsidiary thereof which involves more than $150 million (or
such other amount, established by resolution of the Board of Directors (approved
by Supermajority Approval) from time to time), of the total assets of the
Company and its Subsidiaries taken as a whole, including a sale of the Company
effected by means of a sale of Common Stock, but excluding, however,
dispositions of assets in the ordinary course of business (including, but not
limited to, oil and gas production).

     Section 3.4. Amendments to Articles of Incorporation and Bylaws. The
Company, the Medicor Parties, the ERI Parties and the Belfer Parties shall take
or cause to be taken all lawful action necessary to ensure at all times that the
Company's Articles of Incorporation and Bylaws are at all times consistent with
the provisions of this Agreement.

     Section 3.5. Self-Interested Transactions. The consummation, amendment,
restatement, substitution or modification of any contract, agreement,
transaction or other arrangement between the Company or any Subsidiary of the
Company and any Medicor Person, ERI, any Belfer Person or any Affiliate of any
Medicor Person, ERI or any Belfer Person (a "Self-Interested Transaction") shall
require, except when the economic effect to the Company of any such action (or
set of related actions) is $50,000 or less, the affirmative vote of a majority
of the Disinterested Directors present at a duly called and noticed meeting at
which a quorum is present. "Disinterested Directors" shall include all Directors
not nominated by the Medicor


                                      -11-
<PAGE>


Group, ERI or the Belfer Group which is or whose Affiliate is a party to the
Self-Interested Transaction (other than any Independent Directors).

                                   ARTICLE IV
                                   STANDSTILL

     Section 4.1. Standstill.

          (a) The Medicor Group agrees that from and after the date hereof it
will not, and will not act in concert with any Person so as to form a group (as
such term is defined in Regulation 13D promulgated under the Exchange Act) to,
in any manner, acquire, agree to acquire or make any proposal to acquire,
directly or indirectly, beneficial ownership (as such term is defined in
Regulation 13D promulgated under the Exchange Act) of any additional securities
or debt instruments of the Company or any Subsidiary of the Company without the
consent of ERI, so long as the ERI Parties hold at least 5% of the then
outstanding Common Stock, and the Belfer Group, so long as the Belfer Parties
hold at least 5% of the then outstanding Common Stock. The restrictions set
forth in this Section 4.1(a) shall not apply (i) so long as (A) the Medicor
Parties do not beneficially own more than 30% of the then outstanding Common
Stock or (B) the Medicor Parties, make an offer in writing to the Company's
Board of Directors to acquire for cash all of the outstanding Common Stock not
then held by it and the Board of Directors (including a majority of the
Disinterested Directors) approves the offer after receipt of a written fairness
opinion from a nationally recognized investment banking firm to the effect that
the consideration to be paid in the transaction is fair from a financial point
of view to all shareholders of the Company (other than the offering shareholder)
or (ii) if each of the ERI Parties and the Belfer Parties hold less than 5% of
the then outstanding Common Stock.

          (b) ERI agrees that from and after the date hereof it will not, and
that it will cause its Subsidiaries not to, and will not act in concert with any
Person so as to form a group (as such term is defined in Regulation 13D
promulgated under the Exchange Act) to, in any manner, acquire, agree to acquire
or make any proposal to acquire, directly or indirectly, beneficial ownership
(as such term is defined in Regulation 13D promulgated under the Exchange Act)
of any additional securities or debt instruments of the Company or any
Subsidiary of the Company without the consent of the Medicor Group, so long as
the Medicor Parties hold at least 5% of the then outstanding Common Stock, and
the Belfer Group, so long as the Belfer Parties hold at least 5% of the then
outstanding Common Stock. The restrictions set forth in this Section 4.1(b)
shall not apply (i) so long as (A) ERI does not beneficially own more than 30%
of the then outstanding Common Stock or (B) ERI makes an offer in writing to the
Company's Board of Directors to acquire for cash all of the outstanding Common
Stock not then held by it and the Board of Directors (including a majority of
the Disinterested Directors) approves the offer after receipt of a written
fairness opinion from a nationally recognized investment banking firm to the
effect that the consideration to be paid in the transaction is fair from a
financial point of view to all shareholders of the Company (other than the
offering shareholder) or (ii) if each of the Medicor Parties and the Belfer
Parties hold less than 5% of the then outstanding Common Stock.

          (c) The Belfer Group agrees that from and after the date hereof they
will not, and will not act in concert with any Person so as to form a group (as
such term is defined in Regulation 13D promulgated under the Exchange Act) to,
in any manner, acquire, agree to


                                      -12-
<PAGE>


acquire or make any proposal to acquire, directly or indirectly, beneficial
ownership (as such term is defined in Regulation 13D promulgated under the
Exchange Act) of any additional securities or debt instruments of the Company or
any Subsidiary of the Company without the consent of the Medicor Group, so long
as the Medicor Parties hold at least 5% of the then outstanding Common Stock,
and ERI, so long as the ERI Parties hold at least 5% of the then outstanding
Common Stock. The restrictions set forth in this Section 4.1(c) shall not apply
(i) so long as (A) the Belfer Parties do not beneficially own more than 20% of
the then outstanding Common Stock or (B) the Belfer Parties make an offer in
writing to the Company's Board of Directors to acquire for cash all of the
outstanding Common Stock not then held by it and the Board of Directors
(including a majority of the Disinterested Directors) approves the offer after
receipt of a written fairness opinion from a nationally recognized investment
banking firm to the effect that the consideration to be paid in the transaction
is fair from a financial point of view to all shareholders of the Company (other
than the offering shareholder) or (ii) if each of the Medicor Parties and the
ERI Parties hold less than 5% of the then outstanding Common Stock.

                                   ARTICLE V
                               REGISTRATION RIGHTS

     Section 5.1. Demand Registrations.

          (a) Requests for Registration. Each of the Medicor Group, on behalf of
the Medicor Parties, ERI, on behalf of the ERI Parties, and the Belfer Group, on
behalf of the Belfer Parties, shall have the right to request registration under
the Securities Act of all or part of their Registrable Securities on Form S-1 or
any similar long-form registration or, if available, on Form S-2 or S-3 or any
similar short-form registration ("Short-Form Registrations") in accordance with
this Article V. All registrations requested pursuant to this Section 5.l(a) are
referred to herein as "Demand Registrations."

          (b) Short-Form Registrations. Demand Registrations will be Short-Form
Registrations whenever the Company is permitted to use any applicable short
form. The Company will use its best efforts to make Short-Form Registrations
available for the sale of Registrable Securities. Demand Registration requests
may be for shelf registrations if the Company is then eligible to effect shelf
registrations.

          (c) Restrictions on Demand Registrations. The registration rights
granted under this Section 5.1 are expressly subject to the following terms and
conditions:

               1. The Company will not be obligated to effect any Demand
Registration within six (6) months after the effective date of a previous Demand
Registration.

               2. The Company may postpone for up to ninety (90) days the filing
or the effectiveness of a registration statement for a Demand Registration if
the Company notifies the Party initiating the Demand Registration within fifteen
(15) days after receipt of request for such registration (i) that the Company is
at such time conducting or about to conduct an underwritten public offering of
its securities for its own account and the Board of Directors has determined in
its good faith judgment that such offering would be materially adversely
effected by such registration requested by such Party or (ii) that the Board of
Directors has determined, in


                                      -13-
<PAGE>


its good faith judgment, that such Demand Registration would reasonably be
expected to have an adverse effect on any proposal or plan by the Company or any
of its Subsidiaries to engage in any acquisition of assets (other than in the
ordinary course of business) or any merger, consolidation, tender offer or
similar transaction; provided, that, in such event, the holders of Registrable
Securities initially requesting such Demand Registration will be entitled to
withdraw such request and, if such request is withdrawn, such Demand
Registration will not count as a Demand Registration hereunder and the Company
will pay all Registration Expenses in connection with such request.

               3. Any request for a Demand Registration shall not be otherwise
deemed to be effective unless such request includes the lesser of (i) at least
ten percent (10%) of the Company's outstanding Common Stock or (ii) all of the
Common Stock owned by the Parties making the request. Each request for a Demand
Registration shall specify the approximate number of Registrable Securities
requested to be registered and the anticipated per share price range for such
offering.

               4. The Medicor Parties and the ERI Parties shall each be entitled
to initiate only three (3) Demand Registrations and the Belfer Parties shall be
entitled to initiate only two (2) Demand Registrations to register Registrable
Securities under the terms of this Section 5.1; provided, if one of such Parties
joins in the Demand Registration initiated by the other in accordance with
Section 5.1(c)(5), the initiating Party shall not be deemed to have initiated
the Demand Registration for purposes (and solely for the purposes) of the
limitation contained in this sentence.

               5. If at any time or from time to time any of the Parties shall
request registration of any Registrable Securities in accordance with this
Section 5.1, the Company shall give the other Parties prompt written notice of
the proposed registration. The other Parties shall have the right to join in
such registration by giving notice to the Company within five (5) business days
after such Party receives notice of the proposed registration from the Company
and the Company shall include in such registration the number of Registrable
Securities requested by such other Parties on the same terms and conditions as
the Registrable Securities of the Party initiating the request. If the managing
underwriter or underwriters of a proposed offering for which securities of more
than one of the Parties are included pursuant to this Section 5.1(c)(5) advise
the Company in writing that in its or their good faith judgment the total amount
of securities to be included in such offering exceeds the number which can be
sold in such offering within a price range reasonably acceptable to the Parties,
then in such event the securities to be included in such offering shall be
allocated pro rata among each such Parties and their Permitted Transferees
participating in the offering based upon the number of Shares owned by each such
Party and its Permitted Transferees.

               6. Any registration statement filed on Form S-3 pursuant to Rule
415 of the Securities Act covering Registrable Securities shall be restricted
for use pursuant to a firmly underwritten offering of Common Stock; provided,
however, that a shelf registration statement filed under Rule 415 will not
require a firm commitment underwritten offering for (i) sales of Common Stock
constituting block sales of less than five percent (5%) of the Common Stock
outstanding to institutional investors in solicited transactions, or (ii) sales
into the market


                                      -14-
<PAGE>


in unsolicited brokers transactions if the total amount of shares registered for
sale in this manner involves less than ten percent (10%) of the shares of Common
Stock then outstanding. Each offering of Registrable Securities under this
Section 5.1 pursuant to a shelf registration statement under Rule 415, other
than offers and sales of Common Stock pursuant to subsections (i) and (ii) of
the preceding sentence, shall be treated as a Demand Registration (other than
for purposes of Section 5.1(c)(1)) and must satisfy all requirements for a
Demand Registration.

          (d) Other Registration Rights. The Company will not grant to any
Person the right to request the Company to register any equity securities of the
Company with terms more favorable to such Person than those granted in this
Agreement without the prior written consent of the Medicor Group, ERI and the
Belfer Group.

     Section 5.2. Piggyback Registrations.

          (a) Right to Piggyback. Whenever the Company proposes to register any
of its equity securities under the Securities Act (other than a registration on
Form S-4 or Form S-8 or any successor or similar forms and other than a Demand
Registration pursuant to Section 5.1) and the registration form to be used may
be used for the registration of Registrable Securities (a "Piggyback
Registration"), whether or not for sale for its own account, the Company will
give prompt written notice to the Medicor Group, on behalf of the Medicor
Parties, ERI, on behalf of the ERI Parties, and the Belfer Group, on behalf of
the Belfer Parties, of its intention to effect such a registration and will
include in such registration all Registrable Securities with respect to which
the Company has received written requests for inclusion therein within twenty
(20) days after the receipt of the Company's notice. The Company will use its
reasonable best efforts to include, and to cause the managing underwriters, if
applicable, to include in the proposed offering such Registrable Securities on
the same terms and conditions as the securities of the Company included in such
registration.

          (b) Priority on Primary Registrations. If a Piggyback Registration is
an underwritten primary registration on behalf of the Company, and the managing
underwriters advise the Company in writing that in their opinion the number of
securities requested to be included in such registration exceeds the number
which can be sold in such offering within a price range reasonably acceptable to
the Company, the Company will include in such registration (i) first, the
securities the Company proposes to sell, to the extent of availability and, (ii)
second, all other securities (including the Registrable Securities) requested to
be included in such registration, pro rata among the respective holders thereof
on the basis of the number of securities owned by each such holder.

          (c) Priority on Secondary Registrations. If a Piggyback Registration
is an underwritten secondary registration on behalf of holders of the Company's
securities, and the managing underwriters advise the Company in writing that in
their opinion the number of securities requested to be included in such
registration exceeds the number which can be sold in such offering within a
price range reasonably acceptable to such holders, the securities which can be
included in such registration shall be allocated as follows: (i) first, the
securities (including the Registrable Securities) requested to be included in
such registration by the Persons exercising the Demand Registration, (ii) then,
to the extent of availability, securities to be registered for the account of
the Company and (iii) thereafter, to the extent of availability, to other
security holders


                                      -15-
<PAGE>


exercising piggyback registration rights, pro rata based upon the number of
Shares owned by each such holder.

          (d) Limited Purpose Shelf Registration Statement. In order to
facilitate the exercise by the Medicor Group, ERI and the Belfer Group of their
Piggyback Registration rights, upon request of either the Medicor Group, ERI or
the Belfer Group (any such request shall not constitute a Demand Registration
for purposes of Section 5.1), the Company shall prepare and file with the
Commission one or more registration statements on Form S-3 under Rule 415 of the
Securities Act providing for the resale of Registrable Securities in an amount
of shares to be mutually agreed by Company and the Medicor Group, ERI and the
Belfer Group from time to time, provided, that such registration statement on
Form S-3 shall be restricted for use by the holders of the securities subject to
such registration statement only for participation pursuant to Section 5.2 in a
firmly underwritten public offering of Common Stock proposed by the Company for
the account of the Company or the account of any other security holder.

     Section 5.3. Holdback Agreements.

          (a) If requested in writing by the Company or the managing
underwriters, if any, of any registration effected pursuant to Sections 5.1 or
5.2, the Medicor Group agrees not to and will cause the other Medicor Parties
not to, ERI agrees not to and will cause the other ERI Parties not to, and the
Belfer Group agrees not to and will cause the other Belfer Parties not to effect
any public sale or distribution (including sales pursuant to Rule 144) of equity
securities of the Company, or any securities convertible into or exchangeable or
exercisable for such securities, during the time period reasonably requested by
the managing underwriters, not to exceed seven (7) days prior to and the 180-day
period beginning on the effective date of any underwritten Demand Registration,
any underwritten Piggyback Registration or other underwritten registration by
the Company of its securities (except as part of such underwritten
registration).

          (b) If requested in writing by the managing underwriters of any
registration effected pursuant to Section 5.1 or 5.2, the Company agrees (i) not
to effect any public sale or distribution of its equity securities, or any
securities convertible into or exchangeable or exercisable for such securities,
during the time period reasonably requested by the managing underwriters, not to
exceed seven days prior to and during the 180-day period beginning on the
effective date of any underwritten Demand Registration or any underwritten
Piggyback Registration (except as part of such underwritten registration or
pursuant to registrations on Form S-4 or Form S-8 or any successor forms), and
(ii) to cause each holder of its Common Stock, or any securities convertible
into or exchangeable or exercisable for Common Stock, purchased from the Company
at any time after the date of this Agreement (other than in a registered public
offering), to so agree.

          (c) If the Company has previously filed a registration statement with
respect to Registrable Securities pursuant to Sections 5.1 or 5.2, and if such
previous registration has not been withdrawn or abandoned, the Company will not
file or cause to be effected any other registration of any of its equity
securities or securities convertible or exchangeable into or exercisable for its
equity securities under the Securities Act (except on Form S-4 or Form S-8 or
any successor forms), whether on its own behalf or at the request of any holder
or holders of


                                      -16-
<PAGE>


such securities, until a period of at least ninety (90) days has elapsed from
the effective date of such previous registration.

     Section 5.4. Registration Procedures. Whenever the Medicor Group, on behalf
of the Medicor Parties, ERI, on behalf of the ERI Parties, or the Belfer Group
on behalf of the Belfer Parties has requested that any Registrable Securities be
registered pursuant to this Agreement, the Company will use its best efforts to
effect the registration and the sale of such Registrable Securities in
accordance with the intended method of disposition thereof, and pursuant thereto
the Company will as expeditiously as possible:

          (a) prepare and file with the Commission a registration statement with
respect to such Registrable Securities and thereafter use its reasonable best
efforts to cause such registration statement to become effective (provided that,
before filing a registration statement or prospectus or any amendments or
supplements thereto, the Company will furnish to the counsel selected by the
holders of the Registrable Securities covered by such registration statement
copies of all such documents proposed to be filed, which documents will be
subject to reasonable review of such counsel);

          (b) prepare and file with the Commission such amendments and
supplements to such registration statement and the prospectus used in connection
therewith as may be necessary to keep such registration statement effective for
a period of either (i) not less than six months (subject to extension pursuant
to Section 5.7(b)) or, if such registration statement relates to an underwritten
offering, such longer period as in the opinion of counsel for the underwriters a
prospectus is required by law to be delivered in connection with sales of
Registrable Securities by an underwriter or dealer or (ii) such shorter period
as will terminate when all of the securities covered by such registration
statement have been disposed of in accordance with the intended methods of
disposition by the seller or sellers thereof set forth in such registration
statement (but in any event not before the expiration of any longer period
required under the Securities Act), and to comply with the provisions of the
Securities Act with respect to the disposition of all securities covered by such
registration statement until such time as all of such securities have been
disposed of in accordance with the intended methods of disposition by the seller
or sellers thereof set forth in such registration statement;

          (c) furnish to each seller of Registrable Securities such number of
copies of such registration statement, each amendment and supplement thereto,
the prospectus included in such registration statement (including each
preliminary prospectus) and such other documents as such seller may reasonably
request in order to facilitate the disposition of the Registrable Securities
owned by such seller;

          (d) use its best efforts to register or qualify such Registrable
Securities under such other securities or blue sky laws of such jurisdictions as
any seller reasonably requests and do any and all other acts and things which
may be reasonably necessary or advisable to enable such seller to consummate the
disposition in such jurisdictions of the Registrable Securities owned by such
seller (provided that the Company will not be required to (i) qualify generally
to do business in any jurisdiction where it would not otherwise be required to
qualify but for this subparagraph, (ii) subject itself to taxation in any such
jurisdiction or (iii) consent to general service of process in any such
jurisdiction);


                                      -17-
<PAGE>


          (e) notify each seller of such Registrable Securities, at any time
when a prospectus relating thereto is required to be delivered under the
Securities Act, upon discovery that, or upon the discovery of the happening of
any event as a result of which, the prospectus included in such registration
statement contains an untrue statement of a material fact or omits any fact
necessary to make the statements therein not misleading in the light of the
circumstances under which they were made, and, at the request of any such
seller, the Company will prepare and furnish to such seller a reasonable number
of copies of a supplement or amendment to such prospectus so that, as thereafter
delivered to the purchasers of such Registrable Securities, such prospectus will
not contain an untrue statement of a material fact or omit to state any fact
necessary to make the statements therein not misleading in the light of the
circumstances under which they were made;

          (f) cause all such Registrable Securities to be listed on each
securities exchange on which similar securities issued by the Company are then
listed and, if not so listed, to be listed on the Nasdaq National Market or the
New York Stock Exchange;

          (g) provide a transfer agent and registrar for all such Registrable
Securities not later than the effective date of such registration statement;

          (h) enter into such customary agreements (including underwriting
agreements in customary form for similar offerings) and take all such other
actions as the holders of a majority of the Registrable Securities being sold or
the underwriters, if any, reasonably request in order to expedite or facilitate
the disposition of such Registrable Securities (including, without limitation,
effecting a stock split or a combination of shares);

          (i) make available for inspection by any seller of Registrable
Securities, any underwriter participating in any disposition pursuant to such
registration statement, and any attorney, accountant or other agent retained by
any such seller or underwriter, all financial and other records, pertinent
corporate documents and properties of the Company, and cause the Company's
officers, Directors, employees and independent accountants to supply all
information reasonably requested by any such seller, underwriter, attorney,
accountant or agent in connection with such registration statement;

          (j) otherwise use its reasonable best efforts to comply with all
applicable rules and regulations of the Commission, and make available to its
security holders, as soon as reasonably practicable, an earnings statement
covering the period of at least twelve months beginning with the first day of
the Company's first full calendar quarter after the effective date of the
registration statement, which earnings statement shall satisfy the provisions of
Section 11(a) of the Securities Act and Rule 158 thereunder;

          (k) in the event of the issuance of any stop order, injunction or
other order or requirement suspending the effectiveness of a registration
statement, or of any order suspending or preventing the use of any related
prospectus or suspending the qualification of any securities included in such
registration statement for sale in any jurisdiction, the Company will use its
reasonable best efforts promptly to obtain the withdrawal of such order and to
notify the holders of all of the Registrable Securities covered by the
registration statement of such order;


                                      -18-
<PAGE>


          (l) obtain a cold comfort letter, dated the effective date of such
registration statement (and, if such registration includes an underwritten
public offering, dated the date of the closing under the underwriting
agreement), signed by the Company's independent public accountants in customary
form and covering such matters of the type customarily covered by cold comfort
letters as the holders of a majority of the Registrable Securities being sold
reasonably request (provided that such Registrable Securities constitute at
least 10% of the securities covered by such registration statement);

          (m) provide a legal opinion of the Company's outside counsel, dated
the effective date of such registration statement (and, if such registration
includes an underwritten public offering, dated the date of the closing under
the underwriting agreement), with respect to the registration statement, each
amendment and supplement thereto, the prospectus included herein (including the
preliminary prospectus) and such other documents relating thereto in customary
form and covering such matters of the type customarily covered by legal opinions
of such nature;

          (n) promptly furnish to the managing underwriter, if any, and each
seller of Registrable Securities copies of any written request by the Commission
or any state securities authority for amendments or supplements to a
registration statement or prospectus or for additional information; and

          (o) make reasonably available its employees and personnel and
otherwise provide reasonable assistance to any underwriters in the marketing of
Registrable Securities in any underwritten offering.

     The Company may require each seller of Registrable Securities as to which
any registration is being effected to furnish the Company such information
regarding such seller and the distribution of such securities as the Company may
from time to time reasonably request in writing.

     Section 5.5. Registration Expenses.

          (a) The Company shall pay all Registration Expenses relating to any
registration of Registrable Securities hereunder. "Registration Expenses" shall
mean any and all fees and expenses incident to the Company's performance of or
compliance with this Article V, including, without limitation: (i) Commission,
stock exchange or National Association of Securities Dealers, Inc. registration
and filing fees and all listing fees and fees with respect to the inclusion of
securities on the Nasdaq National Market, (ii) fees and expenses of compliance
with state securities or "blue sky" laws and in connection with the preparation
of a "blue sky" survey, including, without limitation, reasonable fees and
expenses of blue sky counsel, (iii) printing expenses, (iv) messenger and
delivery expenses, (v) fees and disbursements of counsel for the Company, (vi)
with respect to each registration, reasonable fees and disbursements of one
counsel for the selling holders of Shares (selected by the holders making the
Demand Registration request, in the case of a registration pursuant to Section
5.1, and selected by the holders of a majority of the Registrable Securities
included in such registration, in the case of a registration pursuant to Section
5.2) as well as of one local counsel, (vii) fees and disbursements of all
independent public accountants (including the expenses of any audit and/or "cold
comfort"


                                      -19-
<PAGE>


letter) and fees and expenses of other persons, including special experts,
retained by the Company, and (viii) any other fees and disbursements of
underwriters, if any, customarily paid by issuers or sellers of securities.

          (b) Notwithstanding the foregoing, (i) the provisions of this Section
5.5 shall be deemed amended to the extent necessary to cause these expense
provisions to comply with "blue sky" laws of each state in which the offering is
made and (ii) in connection with any registration hereunder, each holder of
Registrable Securities being registered shall pay all underwriting discounts and
commissions and transfer taxes, if any, attributable to the Registrable
Securities included in the offering by such holder.

     Section 5.6. Indemnification.

          (a) The Company agrees to indemnify and hold harmless, to the extent
permitted by law, each holder of Registrable Securities, its officers and
Directors and each Person who controls such holder (within the meaning of the
Securities Act) against any losses, claims, damages, liabilities, joint or
several, to which such holder or any such Director or officer or controlling
person may become subject under the Securities Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions or proceedings, whether
commenced or threatened, in respect thereof) arise out of or are based upon (i)
any untrue or alleged untrue statement of a material fact contained (A) in any
registration statement, prospectus or preliminary prospectus or any amendment
thereof or supplement thereto or (B) in any application or other document or
communication (in this Section 5.6 collectively called an "application")
executed by or on behalf of the Company or based upon written information
furnished by or on behalf of the Company filed in any jurisdiction in order to
qualify any securities covered by such registration statement under the "blue
sky" or securities laws thereof, or (ii) any omission or alleged omission of a
material fact required to be stated therein or necessary to make the statements
therein not misleading, and the Company will reimburse such holder and each such
Director, officer and controlling person for any legal or any other expenses
incurred by them in connection with investigating or defending any such loss,
claim, liability, action or proceeding; provided that the Company shall not be
liable in any such case to the extent that any such loss, claim, damage,
liability (or action or proceeding in respect thereof) or expense arises out of
or is based upon an untrue statement or alleged untrue statement, or omission or
alleged omission, made in such registration statement, any such prospectus or
preliminary prospectus or any amendment or supplement thereto, or in any
application, in reliance upon and in conformity with written information
prepared and furnished to the Company by such holder expressly for use therein
or by such holder's failure to deliver a copy of the registration statement or
prospectus or any amendments or supplements thereto after the Company has
furnished such holder with a sufficient number of copies of the same. In
connection with an underwritten offering, the Company will indemnify such
underwriters, their officers and Directors and each Person who controls such
underwriters (within the meaning of the Securities Act) to the same extent as
provided above with respect to the indemnification of the holders of Registrable
Securities.

          (b) In connection with any registration statement in which a holder of
Registrable Securities is participating, each such holder will furnish to the
Company in writing such information and documents as the Company reasonably
requests for use in connection with


                                      -20-
<PAGE>


any such registration statement or prospectus and, to the extent permitted by
law, will indemnify and hold harmless the Company, its Directors and officers
and each other Person who controls the Company (within the meaning of the
Securities Act) against any losses, claims, damages, liabilities, joint or
several, to which the Company or any such Director or officer or controlling
person may become subject under the Securities Act or otherwise, insofar as such
losses, claims, damages or liabilities (or actions or proceedings, whether
commenced or threatened, in respect thereof) arise out of or are based upon (i)
any untrue or alleged untrue statement of a material fact contained in the
registration statement, prospectus or preliminary prospectus or any amendment
thereof or supplement thereto or in any application or (ii) any omission or
alleged omission of a material fact required to be stated therein or necessary
to make the statements therein not misleading, but only to the extent that such
untrue statement or omission is made in such registration statement, any such
prospectus or preliminary prospectus or any amendment or supplement thereto, or
in any application, in reliance upon and in conformity with written information
prepared and furnished to the Company by such holder expressly for use therein,
and such holder will reimburse the Company and each such Director, officer and
controlling person for any legal or any other expenses incurred by them in
connection with investigating or defending any such loss, claim, liability,
action or proceeding; provided that the obligation to indemnify will be
individual to each holder and will be limited to the net amount of proceeds
received by such holder from the sale of Registrable Securities pursuant to such
registration statement.

          (c) Any Person entitled to indemnification hereunder will (i) give
prompt written notice to the indemnifying party of any claim with respect to
which it seeks indemnification and (ii) unless in such indemnified party's
reasonable judgment a conflict of interest between such indemnified and
indemnifying parties may exist with respect to such claim, permit such
indemnifying party to assume the defense of such claim with counsel reasonably
satisfactory to the indemnified party. If such defense is assumed, the
indemnifying party will not be subject to any liability for any settlement made
by the indemnified party without its consent (but such consent will not be
unreasonably withheld). An indemnifying party who is not entitled to, or elects
not to, assume the defense of a claim will not be obligated to pay the fees and
expenses of more than one counsel for all parties indemnified by such
indemnifying party with respect to such claim, unless in the reasonable judgment
of any indemnified party a conflict of interest may exist between such
indemnified party and any other of such indemnified parties with respect to such
claim.

          (d) The indemnification provided for under this Agreement will remain
in full force and effect regardless of any investigation made by or on behalf of
the indemnified party or any officer, Director or controlling Person of such
indemnified party and will survive the transfer of securities by any holder
thereof. The Company also agrees to make such provisions, as are reasonably
requested by any indemnified party, for contribution to such party in the event
the Company's indemnification is unavailable for any reason.

     Section 5.7. Participation in Underwritten Registrations.

          (a) If requested by the underwriters for any underwritten offering
pursuant to a Demand Registration requested under Section 5.1, the Company shall
enter into a customary underwriting agreement with the underwriters. Such
underwriting agreement shall be


                                      -21-
<PAGE>


satisfactory in form and substance to the Person who requested such registration
and shall contain such representations and warranties by, and such other
agreements on the part of, the Company and such other terms as are generally
prevailing in agreements of that type, including, without limitation,
indemnities and contribution agreements. Such underwriting agreement shall also
contain such representations, warranties, indemnities and contributions by the
participating holders as are customary in agreements of that type. In the case
of a registration pursuant to Section 5.2 hereof, if the Company shall have
determined to enter into any underwriting agreements in connection therewith,
all of the holders' Registrable Securities to be included in such registration
shall be subject to such underwriting agreement. Such underwriting agreement
shall also contain such representations, warranties, indemnities and
contributions by the participating holders as are customary in agreements of
that type.

          (b) Each Person that is participating in any registration hereunder
agrees that, upon receipt of any notice from the Company of the happening of any
event of the kind described in Section 5.4(e) above, such Person will forthwith
discontinue the disposition of its Registrable Securities pursuant to the
registration statement until such Person's receipt of the copies of a
supplemented or amended prospectus as contemplated by such Section 5.4(e). In
the event the Company shall give any such notice, the applicable time period
mentioned in Section 5.4(b) during which a registration statement is to remain
effective shall be extended by the number of days during the period from and
including the date of the giving of such notice pursuant to this paragraph to
and including the date when each seller of a Registrable Security covered by
such registration statement shall have received the copies of the supplemented
or amended prospectus contemplated by Section 5.4(e).

     Section 5.8. Current Public Information. At all times after the Company has
filed a registration statement with the Commission pursuant to the requirements
of either the Securities Act or the Exchange Act, the Company will file all
reports required to be filed by it under the Act and the Exchange Act and the
rules and regulations adopted by the Commission thereunder, and will take such
further action as any holder or holders of Registrable Securities may reasonably
request, all to the extent required to enable such holders to sell Registrable
Securities pursuant to Rule 144.

     Section 5.9. Cooperation. If the Company determines to authorize and/or
issue any capital stock or other debt or equity securities in a public offering,
each of the Parties and their Permitted Transferees agrees to cooperate with the
Company and to take all action necessary to assist the Company in consummating
such transaction.

                                   ARTICLE VI
                               GENERAL PROVISIONS

     Section 6.1. Notices. Any notice required to be given hereunder shall be
sufficient if in writing, and sent by facsimile transmission and by courier
service (with proof of service), hand delivery or certified or registered mail
(return receipt requested and first-class postage prepaid), addressed as
follows:


                                      -22-
<PAGE>


                  If to the Belfer Group:

                           Robert A. Belfer
                           767 Fifth Avenue, 46th Floor
                           New York, New York 10153
                           Fax Number:  (212) 644-2300
                           Phone Number: (212) 644-2200

                  With a copy to:

                           Vinson & Elkins L.L.P.
                           666 Fifth Avenue, 26th Floor
                           New York, New York  10103-0400
                           Attention:  Alan P. Baden
                           Fax Number:  (917) 206-8100
                           Phone Number: (917) 206-8001

                  If to Westport or the Company:

                           Donald D. Wolf,
                           Chairman and Chief Executive Officer
                           1670 Broadway, Suite 2800
                           Denver, CO.  80202
                           Fax Number:  (303) 573-5609
                           Phone Number:  (303) 573-5404

                  If to Westport Energy LLC:

                           Westport Energy LLC
                           c/o Westport Investments Limited
                           Lyford Manor
                           Lyford Cay
                           P.O. Box N-7776
                           Nassau, Bahamas
                           Fax Number:  (242) 362-5788

                  With a copy to:

                           Akin Gump Strauss Hauer & Feld LLP
                           1700 Pacific Avenue, Suite 4100
                           Dallas, Texas  75201-4675
                           Attention:  Michael E. Dillard, P.C.
                           Fax Number:  (214) 969-4343
                           Phone Number:  (214)  969-2800


                                      -23-
<PAGE>


                  And to:

                           Michael Russell
                           Dr. Richard J. Haas Partners
                           Dukes Court
                           32 Duke Street, St. James's
                           London, SW1Y 6DF
                           Fax Number:  020.7.321.5242
                           Phone Number:  020.7.321.5200

                  If to ERI Investments, Inc.:

                           Johanna G. O'Loughlin

                           Vice President, General Counsel and Secretary
                           ERI Investments, Inc.
                           One Oxford Centre, Suite 3300

                           Pittsburgh, PA  15219
                           Telephone:  (412) 553-7760
                           Telecopy:  (412) 553-5970

                  With a copy to:

                           Stephen W. Johnson, Esquire
                           Reed Smith LLP
                           435 Sixth Avenue
                           Pittsburgh, PA  15219-1886
                           Telephone:  (412) 288-3131
                           Telecopy:  (412) 288-3053

                  If to the Medicor Group:

                           Medicor Foundation
                           c/o Jura Trust AG
                           Mitteldorf 1
                           Postfach 838
                           FL-9490 Vaduz, Liechtenstein

                  With a copy to:

                           Kenneth S. Witt
                           Greenberg Traurig, LLP
                           1200 17th Street, Suite 2400
                           Denver, CO  80202
                           Telephone:  (303) 572-6510
                           Telecopy:  (303) 572-6540


                                      -24-
<PAGE>


or to such other address as any party shall specify by written notice so given,
and such notice shall be deemed to have been delivered as of the date so
telecommunicated, personally delivered or mailed.

     Section 6.2. Assignment; Binding Effect; Benefit. Any Party that Transfers
to a Permitted Transferee shall promptly give written notice of such Transfer to
the Parties pursuant to Section 6.1 and shall deliver to such Parties a copy of
the written agreement pursuant to which the Permitted Transferee has agreed to
be bound by the terms of this Agreement. Other than Transfers to Permitted
Transferees, neither this Agreement nor any of the rights, interests or
obligations hereunder shall be assigned by any of the Parties or their Permitted
Transferees without the prior written consent of the other Parties; provided,
that the Medicor Parties, the ERI Parties and the Belfer Parties may assign all
or a portion of their rights under Article V in connection with any Transfer of
Registrable Securities made in accordance with this Agreement if immediately
after the Transfer, the transferee beneficially owns at least ten percent (10%)
of the Common Stock of the Company then outstanding, in which event each
transferee will have rights and obligations under Article V as if it was a party
to this Agreement to the extent of such assignment. Subject to the preceding
sentence, this Agreement shall be binding upon and shall inure to the benefit of
the parties hereto and their respective successors and assigns. Notwithstanding
anything contained in this Agreement to the contrary, nothing in this Agreement,
express or implied, is intended to confer on any person other than the parties
hereto or their respective heirs, successors, executors, administrators and
assigns any rights, remedies, obligations or liabilities under or by reason of
this Agreement.

     Section 6.3. Entire Agreement. The Merger Agreement, this Agreement, the
exhibits and schedules hereto and any certificate delivered by the parties in
connection herewith constitute the entire agreement among the parties with
respect to the subject matter hereof and supersede all prior agreements and
understandings (oral and written) among the parties with respect thereto.

     Section 6.4. Amendment. No amendment, modification or waiver of this
Agreement shall be effective against any Party unless it shall be in writing and
signed by such Party. Notwithstanding the foregoing, Exhibit A shall be amended
or modified from time to time to reflect Transfers to Permitted Transferees by
giving written notice of such Transfers to the Parties pursuant to Section 6.1.

     Section 6.5. Governing Law; Jurisdiction. This Agreement shall be governed
by and construed in accordance with the laws of the State of Nevada without
regard to its rules of conflict of laws. The Parties agree that any suit, action
or proceeding arising out of, or with respect to, this Agreement or any judgment
entered by any court in respect thereof may be brought only in the courts of the
State of Nevada or the federal district courts located within the State of
Nevada and the Parties hereby accept the exclusive jurisdiction of those courts
for the purpose of any suit, action or proceeding.

     Section 6.6. Counterparts. This Agreement may be executed by the parties
hereto in separate counterparts, each of which when so executed and delivered
shall be an original, but all such counterparts shall together constitute one
and the same instrument. Each counterpart may


                                      -25-
<PAGE>


consist of a number of copies of this Agreement, each of which may be signed by
less than all of the parties hereto, but together all such copies are signed by
all of the parties hereto.

     Section 6.7. Headings. Headings of the Articles and Sections of this
Agreement are for the convenience of the parties only and shall be given no
substantive or interpretive effect whatsoever.

     Section 6.8. Interpretation. In this Agreement, unless the context
otherwise requires: (i) words describing the singular number shall include the
plural and vice versa; (ii) "including" shall mean including, without
limitation; (iii) words denoting any gender shall include all genders; and (iv)
words denoting natural persons shall include corporations and partnerships and
vice versa.

     Section 6.9. Incorporation of Exhibits and Schedules. All exhibits and
schedules hereto are hereby incorporated herein and made a part hereof for all
purposes as if fully set forth herein.

     Section 6.10. Severability. Any term or provision of this Agreement which
is invalid or unenforceable in any jurisdiction shall, as to that jurisdiction,
be ineffective to the extent of such invalidity or unenforceability without
rendering invalid or unenforceable the remaining terms and provisions of this
Agreement or otherwise affecting the validity or enforceability of any of the
terms or provisions of this Agreement in any other jurisdiction. If any
provision of this Agreement is so broad as to be unenforceable, the provision
shall be interpreted to be only so broad as is enforceable.

     Section 6.11. Enforcement of Agreement. The Parties hereto agree that
irreparable damage would occur in the event that any of the provisions of this
Agreement were not performed in accordance with its specific terms or was
otherwise breached. It is accordingly agreed that the Parties and their
Permitted Transferees shall be entitled to an injunction or injunctions to
prevent breaches of this Agreement and to enforce specifically the terms and
provisions hereof in any court, this being in addition to any other remedy to
which they may be entitled at law or in equity.

     Section 6.12. Confidentiality. None of the Medicor Group, their Affiliates,
employees, agents or representatives, ERI, its Affiliates, employees, agents or
representatives nor the Belfer Group, their Affiliates, agents or
representatives shall disclose to any third party any information obtained about
the Company or its operations or business which it may have acquired pursuant to
this Agreement, the Original Shareholders Agreement, the Amended Shareholders
Agreement or the Second Amended and Restated Shareholders Agreement without the
prior written consent of the Company; provided, that any information that is
otherwise publicly available, without breach of this provision, or has been
obtained from a third party without a breach of such third party's duties, shall
not be deemed confidential information.

     Section 6.13. Termination. This Agreement shall terminate and shall cease
to be binding on the Parties upon the earliest to occur of:


                                      -26-
<PAGE>


          (a) with respect to any Party and its Permitted Transferees, the date
on which such Party and its Permitted Transferees cease to own at least 5.0% of
the outstanding Common Stock; and

          (b) with respect to any Party and its Permitted Transferees, the date
on which such Party and its Permitted Transferees cease to own at least 25% of
the Common Stock owned by them as of the Effective Time; and

          (c) the date on which all of the Parties who are then bound hereby
mutually consent to terminate this Agreement in writing;

provided, however, notwithstanding the provisions of Section 6.13 (a), (b) and
(c) above, the provisions of Article V shall continue in effect with respect to
a Party and its Permitted Transferees as long as it holds Registrable Securities
and the provisions of Section 6.12 shall not terminate.

     Section 6.14. Belfer Group Representative. Robert A. Belfer shall be the
initial Belfer Group representative (the "Belfer Group Representative"). The
Belfer Group Representative may be changed by delivery of a written notification
delivered to the parties hereto and executed by all of the members of the Belfer
Group. Each member of the Belfer Group hereby appoints the person or entity who
is, from time to time, duly appointed under this Section 6.14 as the Belfer
Group Representative to give any consent or approval, exercise any right or take
any action contemplated under this Agreement on behalf of the Belfer Group. The
members of the Belfer Group shall be so bound by the Belfer Group Representative
and the parties to this Agreement shall be entitled to rely on the actions taken
by the Belfer Group Representative contemplated by this Agreement.

     Section 6.15. Medicor Group Representative. Michael Russell shall be the
initial Medicor Group representative (the "Medicor Group Representative"). The
Medicor Group Representative may be changed by delivery of a written
notification delivered to the parties hereto and executed by all of the members
of the Medicor Group. Each member of the Medicor Group hereby appoints the
person or entity who is, from time to time, duly appointed under this Section
6.15 as the Medicor Group Representative to give any consent or approval,
exercise any right or take any action contemplated under this Agreement on
behalf of the Medicor Group. The members of the Medicor Group shall be so bound
by the Medicor Group Representative and the parties to this Agreement shall be
entitled to rely on the actions taken by the Medicor Group Representative
contemplated by this Agreement. The inclusion of WELLC and Medicor in a group,
referenced in this Agreement as the Medicor Group, and the appointment by WELLC
and Medicor of a Medicor Group Representative, as set forth above in this
Section 6.15, are merely for administrative convenience. Each of Medicor and
WELLC is a distinct legal entity, and neither Medicor nor WELLC controls the
other or is under the common control of a third party.

     Section 6.16. Effective Time. Notwithstanding anything herein to the
contrary, this Agreement shall become effective upon the transfer by WELLC of
not less than nine million of its shares of Common Stock to Medicor (the
"Effective Time"). The representations and warranties contained herein shall be
deemed to have been made as of the Effective Time. If the above mentioned
transfer by WELLC to Medicor does not occur on or before April 15, 2003 for


                                      -27-
<PAGE>


any reason, this Agreement shall terminate and the Second Amended and Restated
Shareholders Agreement shall remain in effect.






                                      -28-
<PAGE>


     IN WITNESS WHEREOF, the parties have executed this Third Amended and
Restated Shareholders Agreement and caused the same to be duly delivered on
their behalf as of the day and year first written above, to be effective as of
the Effective Date.

                                  WESTPORT RESOURCES
                                  CORPORATION

                                  By: /s/ Barth E. Whitham
                                      -----------------------------------------
                                      Name:  Barth E. Whitham
                                      Title: President and
                                             Chief Operating Officer


                                  WESTPORT ENERGY LLC:

                                  By: WESTPORT INVESTMENTS LIMITED, its
                                      Managing Member

                                      By: /s/ Robert A. Haas
                                          ------------------------------------
                                          Name:   Robert A. Haas
                                          Title:  Vice President


                                  ERI INVESTMENTS, INC.:

                                  By: /s/ Kenneth J. Kubacki
                                      -----------------------------------------
                                      Name:   Kenneth J. Kubacki
                                      Title:  Vice President


                                  MEDICOR FOUNDATION:

                                  By: /s/ Ursula Haas
                                      -----------------------------------------
                                      Name:  Ursula Haas
                                      Title: President

                                  By: /s/ Michael Russell
                                      -----------------------------------------
                                      Name:  Michael Russell
                                      Title: Member of Council


                                      -29-
<PAGE>


                                  /s/ Robert A. Belfer
                                  ---------------------------------------------
                                  ROBERT A. BELFER


                                  /s/ Jack Saltz
                                  ---------------------------------------------
                                  JACK SALTZ


                                  SALTZ INVESTMENT GROUP, LLC:

                                  By: /s/ Jack Saltz
                                      -----------------------------------------
                                      Name:    Jack Saltz
                                      Title:   Manager and Member


                                  JACK & ANITA SALTZ FOUNDATION:

                                  By: /s/ Jack Saltz
                                      -----------------------------------------
                                      Name:  Jack Saltz
                                      Title: President


                                  THE ROBERT A. AND RENEE E. BELFER
                                  FAMILY FOUNDATION:

                                  By: /s/ Robert A. Belfer
                                      -----------------------------------------
                                      Name:  Robert A. Belfer
                                      Title: Trustee and Donor


                                  BELFER CORP.:

                                  By: /s/ Robert A. Belfer
                                      -----------------------------------------
                                      Name:   Robert A. Belfer
                                      Title:  President


                                      -30-
<PAGE>


                                  BELWEST PETROLEUM, INC.:

                                  By: /s/ Robert A. Belfer
                                      -----------------------------------------
                                      Name:    Robert A. Belfer
                                      Title:   President


                                  A&B INVESTORS, INC.:

                                  By: /s/ Robert A. Belfer
                                      -----------------------------------------
                                      Name:    Robert A. Belfer
                                      Title:   ________________________________


                                  RENEE HOLDINGS PARTNERSHIP, L.P.:

                                  By: /s/ Robert A. Belfer
                                      -----------------------------------------
                                      Name:    Robert A. Belfer
                                      Title:   General Partner


                                  THE LAURENCE D. BELFER FAMILY FOUNDATION:

                                  By: /s/ Laurence D. Belfer
                                      -----------------------------------------
                                      Name:    Laurence D. Belfer
                                      Title:   Trustee and Donor


                                  LDB CORP.:

                                  By: /s/ Laurence D. Belfer
                                      -----------------------------------------
                                      Name:    Laurence D. Belfer
                                      Title:   President


                                      -31-
<PAGE>


                                  ROBERT A. BELFER 1990 FAMILY TRUST:

                                  By: /s/ Laurence D. Belfer
                                      -----------------------------------------
                                      Name:    Laurence D. Belfer
                                      Title:   Trustee


                                  VANTZ LIMITED PARTNERSHIP:

                                  By: VANTZ LLC
                                      Its General Partner

                                      By: /s/ Laurence D. Belfer
                                          -------------------------------------
                                          Name:  Laurence D. Belfer
                                          Title:  _____________________________


                                  LDB TWO CORP.:

                                  By: /s/ Laurence D. Belfer
                                      -----------------------------------------
                                      Name:   _________________________________
                                      Title:  _________________________________


                                  BELFER TWO CORP.:

                                  By: /s/ Robert Belfer
                                      -----------------------------------------
                                      Name:    Robert Belfer
                                      Title:   President


                                      -32-
<PAGE>


                                  LIZ PARTNERS, L.P.

                                  By: Liz Associates LLC,
                                      Its General Partner

                                      By: /s/ Robert Belfer
                                          -------------------------------------
                                          Name:  Robert Belfer
                                          Title: Managing Member of Liz
                                                 Associates LLC


                                      -33-
<PAGE>


                                    EXHIBIT A

                              CERTAIN STOCKHOLDERS
                              --------------------

Jack Saltz
Saltz Investment Group, LLC
Jack & Anita Saltz Foundation
The Robert A. and Renee E. Belfer Family Foundation,
Robert A. Belfer
Belfer Corp.
Belwest Petroleum, Inc.
A&B Investors, Inc.
Renee Holdings Partnership, L.P.
The Laurence D. Belfer Family Foundation
LDB Corp.
Robert A. Belfer 1990 Family Trust
Vantz Limited Partnership
LDB Two Corp. (a Permitted Transferee of the Shares previously held by Laurence
    D. Belfer)
Belfer Two Corp. (a Permitted Transferee of the Shares previously held by Renee
    E. Belfer)
Liz Partners, L.P. (a Permitted Transferee of the Shares previously held by
   Elizabeth K. Belfer, which includes Shares distributed pursuant to the
   expiration of the two trusts for the benefit of Elizabeth K. Belfer (T6 and
   T7))


                                      -34-
<PAGE>


                                  SCHEDULE 2.2

                         OWNERSHIP - EACH MEDICOR PERSON


                                                  Ownership of Common Stock
            Stockholder                             as of the date hereof
            -----------                             ---------------------

            Medicor Foundation                             11,000,000
            Westport Energy LLC                             3,238,001


                                      -35-


<PAGE>


                                  SCHEDULE 2.3

                            OWNERSHIP -- ERI PARTIES
                            ------------------------


                                             Ownership of Common Stock
           Stockholder                          as of the date hereof
           -----------                          ---------------------

       ERI Investments, Inc.                        13,911,152


                                      -36-
<PAGE>


                                  SCHEDULE 2.4

                         OWNERSHIP - EACH BELFER PERSON
                         ------------------------------


                                                             Shares held as of
             Stockholder                                      the date hereof
             -----------                                     ------------------

Jack Saltz                                                              6,187

Saltz Investment Group, LLC(1)                                        776,829

Jack & Anita Saltz Foundation(1)                                       62,039

The Robert A. and Renee E. Belfer Family Foundation(2)                263,793

Robert A. Belfer                                                           --

Belfer Corp. (2)                                                    2,753,270

Belwest Petroleum, Inc. (2)                                               136

A&B Investors, Inc. (2)                                                    --

Renee Holdings Partnership, L.P. (2)                                  492,283

The Laurence D. Belfer Family Foundation(3)                             5,077

LDB Corp. (3)                                                         112,552

Robert A. Belfer 1990 Family Trust(3)                                 230,040

Vantz Limited Partnership (3)                                         261,610

LDB Two Corp. (3)                                                     823,031

Belfer Two Corp. (2)                                                1,157,309

Liz Partners, L.P. (2)                                                495,899


(1) c/o Jack Saltz, 767 Fifth Floor Avenue, 46th Floor, New York, New York 10153
(2) c/o Robert A. Belfer, 767 Fifth Avenue, 46th Floor, New York, New York 10153
(3) c/o Laurence D. Belfer, 767 Fifth Avenue, 46th Floor, New York, New York
    10153


                                      -37-