**Exhibit
        4(a)(vi)**
  AGREEMENT
  THIS
        AGREEMENT (“Agreement”), by and between Valcent Products, Inc., an Alberta
        Canada corporation, having a place of business at Suite 420, 475 Howe Street,
        Vancouver, British Columbia, Canada (“VPI”) and Malcolm Glen Kertz, residing at
        6476 Calle Del Sol, El Paso, Texas 79912 (“Kertz”),
  WITNESSETH
  WHEREAS,
        Kertz has entered into, concurrently herewith, a Consulting Agreement and
        an
        Invention License Agreement with MK Enterprises LLC, a Nevada corporation,
        having a place of business at 1300 Clay Street, Winfield, Louisiana 71483
        ( “MK”);
  WHEREAS,
        MK has entered into, concurrently herewith, a Master License Agreement and
        Product Development Agreement with VPI for the commercialization of past,
        present and future new products conceived and developed by MK through the
        efforts of Kertz;
  WHEREAS,
        VPI wishes for the continuation of the services of Kertz in the event of
        the
        termination of the Product Development Agreement;
  NOW,
        THEREFORE, in consideration of the mutual covenants and obligations hereinafter
        set forth and for other good and valuable consideration, the receipt and
        sufficiency of which are hereby acknowledged, the parties hereto agree as
        follows:
  1. The
        Product Development Agreement between VPI and MK has a term of five years
        ( “Five-Year
        Term”).
  2. In
        the
        event that the Product Development Agreement is terminated for whatever reason
        prior to the expiration of the Five Year Term, Kertz agrees to enter into
        agreements with VPI similar to the Consulting Agreement and Invention License
        Agreement for the remaining portion of the Five Year Term of the Product
        Development Agreement.
  3. This
        Agreement shall terminate upon the expiration of the Five Year Term of the
        Product Development Agreement.
  4. If
        a
        dispute arises between the parties regarding this Agreement, the parties
        agree
        to resolve the dispute in the following manner:
  (a) Negotiation.
  (1) The
        parties shall attempt in good faith to resolve any dispute arising out of
        or
        relating to this Agreement promptly by negotiation between executives of
        the
        parties who have authority to settle the controversy. Any party may give
        the
        other party written notice of any dispute not resolved in the normal course
        of
        business. Within 15 days after delivery of the notice, the receiving party
        will
        submit to the other a written response. The notice and the response will
        include
        (i) a statement of each party's position and a summary of arguments supporting
        that position, and (ii) the name and title of the executive who will represent
        that party and of any other person who will accompany the executive. Within
        30
        days after delivery of the disputing party's notice, the executives of both
        parties will meet at a mutually acceptable time and place, and thereafter
        as
        often as they reasonably deem necessary, to attempt to resolve the dispute.
        All
        reasonable requests for information made by one party to the other will be
        honored.
  
  (2) All
        negotiations pursuant to this clause are confidential and will be treated
        as
        compromise and settlement negotiations for purposes of applicable rules of
        evidence.
  (b) Non-binding
        Mediation. If the
        dispute has not been resolved by negotiation within 60 days of the disputing
        party's notice, or if the parties failed to meet within 45 days, the parties
        will endeavor to settle the dispute by mediation under the presently effective
        Center for Public Resources (“CPR”) Model Procedure for Mediation of Business
        Disputes. The neutral third party will be selected from the CPR Panels of
        Distinguished Neutrals with the assistance of CPR.
  (c) Arbitration. Any
        controversy or claim arising out of or relating to this Agreement, or the
        enforcement, breach, termination or validity thereof, that has not been resolved
        by mediation pursuant to the preceding paragraph within 90 days from the
        appointment of a neutral third party will be settled by arbitration in
        accordance with the CPR Rules for Non-Administered Arbitration of Business
        Disputes in effect on the date of this Agreement, by a sole arbitrator. If
        the
        parties cannot agree upon an arbitrator for a panel recommended by CPR, then
        CPR
        will select the arbitrator. Any other choice of law clause to the contrary
        in
        this Agreement notwithstanding, the arbitration will be governed by the United
        States Arbitration Act, 9 U.S.C. § 1-16, and judgment upon the award rendered by
        the Arbitrator may be entered by any court having jurisdiction thereof. The
        place of the arbitration will be Houston, Texas. Insofar as the proceeding
        relates to patents, it will also be governed by 35 U.S.C. § 294, to the extent
        applicable. The arbitrator is not empowered to award trebled, punitive or
        any
        other damages in excess of compensatory damages, and each party irrevocably
        waives any claim to recover any such damages. The arbitrator will make a
        reasoned award. If the result achieved in arbitration by the party instituting
        the arbitration is not more favorable to that party than the last offer made
        by
        the other party during the mediation, the former party will reimburse the
        legal
        fees, expert fees and other expenses reasonably incurred by the latter in
        the
        arbitration.
  5. General
  5.1 Binding
        Agreement. This
        Agreement shall be binding upon the successors and assigns of the parties
        hereto. Nothing contained in this Agreement shall be construed to place the
        parties in the relationship of legal representatives, partners, or joint
        ventures.
  5.2 Applicable
        Law .
        This
        Agreement shall be construed, interpreted and applied in accordance with
        the
        laws of the State of Texas.
  5.3 Notices .
        All
        notices, demands or other writings in this Agreement provided to be given
        or
        made or sent, or which may be given or made or sent, by either party hereto
        to
        the other, shall be deemed to have been fully given or made or sent when
        made in
        writing and deposited in the United States mail, first class, postage prepaid,
        sent certified or registered mail, and addressed to the addresses first
        hereinabove given or at such other address as either party hereto may specify
        by
        notice given in accordance with this paragraph.
  
 
 5.4 Waiver .
        Each
        party covenants and agrees that if the other party fails or neglects for
        any
        reason to take advantage of any of the terms hereof providing for the
        termination of this Agreement, or if, having the right to declare this Agreement
        terminated, such other party shall fail to do, any such failure or neglect
        shall
        not be or be deemed or be construed to be a waiver of any subsequently occurring
        cause for the termination of this Agreement, or as a waiver of any of the
        terms,
        covenants or conditions of this Agreement or the performance thereof. None
        of
        the terms, covenants or conditions of this Agreement can be waived except
        by the
        written consent of the waiving party. Except as otherwise stated herein,
        each of
        the parties hereby waives any claims which it might have against the other
        prior
        to the date of execution of this Agreement.
  5.5 Force
        Majeure .
        Neither
        party hereto shall be liable to the other party for failure or delay in the
        performance of any duties or obligations hereunder due to strikes, lockouts,
        acts of God, acts of war, fire, flood, explosions, embargo, litigation or
        labor
        disputes, Government or any other laws and regulations, or any other cause
        beyond the control or without the fault of such party.
  5.6 Scope
        of Agreement .
        This
        Agreement constitutes the entire agreement between the parties pertaining
        to the
        subject matter hereof.
  5.7 Construction .
        The
        parties acknowledge that each party and its counsel have reviewed and revised
        this Agreement and that the normal rule of construction to the effect that
        any
        ambiguities are to be resolved against the drafting party shall not be employed
        in the interpretation of this Agreement or any amendments or exhibits
        hereto.
  5.8 Headings .
        The
        subject headings of the paragraphs of this Agreement are included for purposes
        of convenience only, and shall not effect the construction or interpretation
        of
        any of its provisions.
  5.9 Counterparts .
        This
        Agreement may be executed in one or more counterparts, and also executed
        shall
        constitute one agreement, binding on both parties hereto, notwithstanding
        that
        both parties are not signatory to the same counterpart.
  5.10 Severability .
        If any
        part or parts of this Agreement are found to be illegal or unenforceable,
        the
        remainder shall be considered severable, shall remain in full force and effect,
        and shall be enforceable.
  5.11 Further
        Documents .
        Each of
        the parties shall take all necessary actions, including the execution and
        delivery of all necessary documents or instruments, as may be reasonably
        requested by the other party in order to effectuate the intent of this
        Agreement.
   
  IN
        WITNESS WHEREOF, the parties hereto have executed this Agreement in duplicate
        originals, individually, or by their duly authorized officers or
        representatives, as of the date of the last party to execute this
        Agreement.
  VALCENT
                PRODUCTS, INC.WITNESS:
              By:
              /s/Name:
                Title:
                Date:




Malcolm
                Glen KertzMalcolm
                Glen Kertz
              
              Date: