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                                                                  EXHIBIT 10.30

                             SECURED PROMISSORY NOTE

$4,500,000                                                    February 26, 2004


         FOR VALUE RECEIVED, Knox Gas, LLC, a Delaware limited liability company
with a principal place of business at 111 Presidential Blvd., Suite 158A, Bala
Cynwyd, PA 19004 (the "Borrower"), hereby promises to pay to Continental
Southern Resources, Inc., a Nevada corporation with a principal place of
business at 1001 Fannin Street, Suite 1700, Houston, Texas 77010 (the "Lender"),
the principal sum of Four Million Five Hundred Thousand Dollars (US $4,500,000),
together with interest on the unpaid principal balance from time to time
outstanding, from the date hereof until maturity at a fixed rate per annum equal
to four percent (4%) (the "Stated Rate"). Interest on this Note shall be
calculated at an annual rate based on the actual number of days elapsed in an
actual calendar year (365 days or 366 days in a leap year, as may be
applicable).

         Principal and interest under this Note shall be due and payable as
follows:

         $500,000 plus accrued and unpaid interest shall be paid on or before
March 27, 2004; $1,000,000 plus accrued and unpaid interest shall be paid on or
before April 27, 2004; $1,000,000 plus accrued and unpaid interest shall be paid
on or before June 27, 2004; and $2,000,000 plus accrued and unpaid interest
shall be paid on or before August 27, 2004.

         All past due principal of, and interest on, this Note shall accrue
interest from the date due until the date it is paid at the lower of (i) 4% plus
the Stated Rate per annum and (ii) the maximum rate allowed by law.

         The Borrower shall have the right, from time to time, without premium
or penalty, to prepay the indebtedness evidenced by this Note, in full or in
part.

         The obligation of the Borrower for payment of principal, interest and
all other sums hereunder is secured by that certain Interest Pledge Agreement,
dated as of even date herewith, between the Borrower and the Lender (the "Pledge
Agreement").

         All payments (including prepayments) to be made by the Borrower
hereunder, whether on account of principal, interest or otherwise, shall be made
without set off or counterclaim and shall be made on or prior to the due date
set forth above to the Lender at the address set forth above, or such other
place as the Lender may from time to time designate in writing. If any payment
or action to be made or taken hereunder shall be stated to be or become due on a
day that is not a business day, such payment or action shall be made or taken on
the next following business day and such extension of time shall be included in
computing interest or fees, if any, in connection with such payment or action.

         "Event of Default," wherever used herein, means any one of the
following events (whatever the reason for such Event of Default and whether it
shall be voluntary or involuntary or be effected by operation of law or pursuant
to any judgment, decree or order of any court or any order, rule or regulation
of any governmental authority):

         (a) default in the payment of the principal sum of this Note, and any
interest accrued thereon, when such principal and interest becomes due and
payable (whether by acceleration or otherwise), or

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         (b) the entry by a court having jurisdiction in the premises of (A) a
decree or order for relief in respect of the Borrower in an involuntary case or
proceeding under any applicable Federal or State bankruptcy, insolvency,
reorganization or other similar law or (B) a decree or order adjudging the
Borrower a bankrupt or insolvent, or approving as properly filed a petition
seeking reorganization, arrangement, adjustment or composition of or in respect
of the Borrower under any applicable Federal or State law, or appointing a
custodian, receiver, liquidator, assignee, trustee, sequestrator or other
similar official of the Borrower or of any substantial part of its property, or
ordering the winding up or liquidation of its affairs, and the continuance of
any such decree or order for relief or any such other decree or order unstayed
and in effect for a period of 90 consecutive days; or

         (c) the commencement by the Borrower of a voluntary case or proceeding
under any applicable Federal or State bankruptcy, insolvency, reorganization or
other similar law or of any other case or proceeding to be adjudicated a
bankrupt or insolvent, or the consent by it to the entry of a decree or order
for relief in respect of the Borrower in an involuntary case or proceeding under
any applicable Federal or State bankruptcy, insolvency, reorganization or other
similar law or to the commencement of any bankruptcy or insolvency case or
proceeding against it, or the filing by it of a petition or answer or consent
seeking reorganization or relief under any applicable Federal or State law, or
the consent by it to the filing of such petition or to the appointment of or
taking possession by a custodian, receiver, liquidator, assignee, trustee,
sequestrator or similar official of the Borrower or of any substantial part of
its property, or the making by it of an assignment for the benefit of creditors,
or the admission by it in writing of its inability to pay its debts generally as
they become due, or the taking of corporate action by the Borrower in
furtherance of any such action.

         Upon the occurrence of an Event of Default, the entire amount of the
indebtedness evidenced by this Note shall be immediately due and payable. Upon
the acceleration of the obligations evidenced by this Note and failure by the
Borrower to pay amounts then due hereunder, Lender may proceed to protect,
exercise and enforce all of its rights and remedies under this Note, the Pledge
Agreement and that certain Interest Purchase Agreement, dated as of even date
herewith, between the Borrower and the Lender and applicable law. The remedies
provided in this Note are cumulative and concurrent, may be pursued in any
order, separately, successively or together, may be exercised as often as
occasion therefor may arise, and shall be in addition to, and not in
substitution for, the rights and remedies that would otherwise be vested in the
Lender for the recovery of damages, or otherwise, in the event of a breach of
any of the undertakings of the Borrower hereunder. This Note may not be
modified, altered or amended, except by an agreement in writing signed by the
Borrower and the Lender.

         It is the intention of the parties hereto to conform strictly to usury
laws applicable to the holder of this Note. Accordingly, if the transactions
contemplated hereby would be usurious under applicable law (including the laws
of the United States of America and the State of Texas), then, in that event,
notwithstanding anything to the contrary in this Note, it is agreed as follows:
(i) the aggregate of all consideration which constitutes interest under law
applicable to the holder of this Note that is contracted for, taken, reserved,
charged or received under this Note shall under no circumstances exceed the
maximum amount allowed by such applicable law; (ii) in the event that the
maturity of this Note is accelerated by reason of an election of the holder of
this Note resulting from any Event of Default, or in the event of any permitted
prepayment, then such consideration that constitutes interest under law
applicable to the holder of this Note may never include more than the maximum
amount allowed by such applicable law, and (iii) excess interest, if any,
provided for


                                       2

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in this Note or otherwise shall be canceled automatically and, if theretofore
paid, shall be credited by the holder of this Note on the principal amount of
this Note (or, to the extent that the principal amount of this Note shall have
been or would thereby be paid in full, refunded by the holder of this Note to
the Borrower). The right to accelerate the maturity of this Note does not
include the right to accelerate any interest that has not otherwise accrued on
the date of such acceleration, and the holder of this Note does not intend to
collect any unearned interest in the event of acceleration. All sums paid or
agreed to be paid to the holder of this Note for the use, forbearance or
detention of sums included in this Note shall, to the extent permitted by
applicable law, be amortized, prorated, allocated and spread throughout the full
term of this Note until payment in full so that the rate or amount of interest
on account of the indebtedness under this Note does not exceed the applicable
usury ceiling, if any. As used in this paragraph, the term "applicable law"
shall mean the law of the State of Texas.

         All reasonable attorney's fees and expenses and other reasonable
out-of-pocket costs incurred by the Payee in connection with the collection of
this Note subsequent to an Event of Default (as defined herein) shall become
amounts due and owing under the terms of this Note in addition to all other
amounts owing pursuant to the other provisions of this Note.

         Borrower hereby waives demand, presentment for payment, protest, notice
of protest, notice of intention to accelerate the indebtedness hereunder, notice
of the acceleration of the indebtedness hereunder and filing of suit and
diligence in collecting this Note or enforcing of any of the rights of Lender.

         This Note shall bind the Borrower and its successors and assigns, and
the benefits hereof shall inure to the benefit of the Lender and its successors
and assigns, except that Borrower may not sell, assign or transfer this Note or
any portion hereof without obtaining the prior written consent of the Lender.
All references herein to the "Borrower" and the "Lender" shall be deemed to
apply to the Borrower and the Lender, respectively, and their respective
successors and assigns.

         This Note and any other documents delivered in connection herewith and
the rights and obligations of the parties hereto and thereto shall for all
purposes be governed by and construed and enforced in accordance with the
internal laws of the State of Texas without giving effect to its conflicts of
law principles.

         IN WITNESS WHEREOF, the undersigned, intending to be legally bound
hereby, has executed this Note as of the date first written above with the
intention that this Note shall constitute a sealed instrument.

                                  KNOX GAS, LLC

                                  By:  /s/ ERNEST BARTLETT
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                                  Name:  Ernest Bartlett
                                  Title: FEQ Investments, Managing Member