Document:

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                                                                    EXHIBIT 10.7

                                 PROMISSORY NOTE

$56,411,000                                                         May 26, 1999

     CMS OIL AND GAS COMPANY, a corporation duly organized and existing in good
standing under the laws of the State of Michigan (the "Borrower"), for value
received, hereby promises to pay to the order of CMS ENERGY CORPORATION, a
Michigan corporation (the "Lender"), the principal sum of Fifty-Six Million Four
Hundred and Eleven Thousand Dollars ($56,411,000) on April 15, 2009.

     The Borrower promises to pay interest on the unpaid principal balance of
the loan made hereunder commencing on April 15, 1999 to the maturity date of
such loan, at a rate per annum equal to the Eurodollar Rate plus two percent for
the most recent quarter (the "Borrowing Rate"), payable quarterly in arrears and
on such maturity date, provided, however, that for the period April 15, 1999 to
April 14, 2004 interest shall be determined and added to the principal balance
of this note on such quarterly dates rather than being paid on such dates. Any
principal not paid when due shall bear interest from maturity until paid in
full, payable upon demand, at a rate per annum equal to 120% of the Borrowing
Rate. Interest shall be calculated on the basis of a year of 360 days and actual
days elapsed.

     All payments hereunder shall be made in lawful money of the United States
and in immediately available funds. Any extension of time for the payment of the
principal of this note resulting from the due date falling on a Saturday, Sunday
or legal holiday shall be included in computation of interest.

     If (i) any sum payable on any liability of the Borrower to the Lender
hereunder shall not be paid when due and such default shall continue for 30
consecutive days; or (ii) the Borrower shall default on any obligation for
repayment of borrowed money and the holder of such borrowed money shall
accelerate the due date thereof, the Lender may, at its option, declare the
principal and interest on this note immediately due and payable, without
protest, presentment, notice or demand, all of which the Borrower hereby waives.
The Borrower agrees to pay on demand all expenses, including reasonable
attorneys fees, the Lender may incur in connection with the enforcement of this
note.

     The indebtedness evidenced by this note (including the obligations
described in the preceding paragraph) and any renewals or extension hereof,
shall at all times be wholly subordinate and junior in right of payment to any
and all present and future indebtedness, obligations and liabilities of the
Borrower pursuant to the Credit Agreement dated as of May 26, 1999 among the
Borrower, the banks now or hereafter parties thereto, the syndication agent and
documentation agent thereto, and The First National Bank of Chicago, as Agent,
as such Credit Agreement is amended, modified, restated or refinanced from time
to time (the "Credit Agreement") and all renewals or increases therein, and
further including without limitation all reimbursement obligations pursuant to
any letters of credit issued pursuant thereto and all

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obligations pursuant to any promissory notes issued pursuant thereto, all
amounts accruing after the filing of any petition in bankruptcy or similar loss,
whether or not such amount is an allowable claim, all guarantees, all guarantees
for any of the foregoing and all rights and remedies of the holders of any of
the foregoing (herein called a "Superior Indebtedness"), in the manner and with
the force and effect hereafter set forth:

         (1) In the event of any liquidation, dissolution, or winding up of the
         Borrower, or of any execution, receivership, insolvency, bankruptcy,
         liquidation, reorganization or other similar proceeding relative to the
         Borrower or its property; all Superior Indebtedness shall first be paid
         in full in cash or cash equivalents before any payment is made upon the
         indebtedness evidenced by this note; and in any such event any payment
         or distribution of any kind or character, whether in cash, property or
         securities (other than in securities, including securities, or other
         evidences of indebtedness, the payment of which is subordinated to the
         payment of all Superior Indebtedness which may at the time be
         outstanding in the same manner as all the subordinated notes are
         subordinated to the Superior Indebtedness, but only to the extent the
         court awarding or permitting the distribution of such securities states
         that in doing so it is giving effect to the subordination of this note
         to the Superior Indebtedness set forth herein) which shall be made upon
         or in respect of this note shall be paid over to the holders of
         Superior Indebtedness, pro rata, for application in payment thereof
         unless and until such Superior Indebtedness shall have been paid or
         satisfied in full;

         (2) In the event that this note is declared or becomes due and payable
         because of the occurrence of any event of default hereunder or
         otherwise than at the option of the Borrower, under circumstances when
         the forgoing clause (1) shall not be applicable, the Lender shall be
         entitled to payments only after there shall first have been paid in
         full in cash or cash equivalents all Superior Indebtedness outstanding
         at the time this note so becomes due and payable because of any such
         event, or payment shall have been made provided for in a manner
         satisfactory to the holders of such Superior Indebtedness; and

         (3) During the continuance of any default with respect to any Superior
         Indebtedness permitting the holders thereof to accelerate the maturity
         of such Superior Indebtedness, no payment of principal, premium or
         interest or other amounts shall be made on this note, unless permitted
         by the Subordination Agreement (as defined below).

         In the event that, notwithstanding the foregoing, any payment or
distribution of assets or securities of the Borrower of any kind or character,
whether in cash, property or securities, shall be received by any trustee, agent
or payment agent or the holders of this note (or, if the borrower of any
subsidiary or affiliate of the Borrower is acting as payment agent, money assets
or securities shall be segregated or held in trust) on account of principal of,
premium on, interest on or other amounts with respect to this note contrary to
terms hereof, such payment or distribution shall be received, segregated from
other funds, and held in trust by such trustee, agent, paying agent or holder
for the benefit of, and shall immediately be paid over to, the holders of
Superior Indebtedness or their representative, ratably according to the
respective amounts of Superior Indebtedness held or represented by each.

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     The Lender undertakes and agrees for the benefit of each holder of Superior
Indebtedness to execute, verify, deliver and file any proofs of claim which any
holder of Superior Indebtedness may at any time require in order to prove and
realize upon any rights or claims pertaining to this note and to effectuate the
full benefit of the subordination contained herein; and upon failure of the
Lender so to do, any such holder of Superior Indebtedness shall be deemed to be
irrevocably appointed the agent and attorney-in-fact of the Lender to execute,
verify, deliver and file any such proofs of claim.

     No right of any holder of any Superior Indebtedness to enforce
subordination as herein provided shall at any time or in any way be affected or
impaired by any failure to act on the part of the Borrower or the holders of
Superior Indebtedness, or by any noncompliance by the Borrower with any of the
terms, provisions and covenants of this note or the agreement under which they
are issued, regardless of any knowledge thereof that any holder of Superior
Indebtedness may have or be otherwise charged with.

     The Borrower agrees, for the benefit of the holders of Superior
Indebtedness, that in the event that this note is declared due and payable
before its expressed maturity because of the occurrence of a default hereunder,
(i) the Borrower will give prompt notice in writing of such happening to the
holders of Superior Indebtedness, and (ii) all Superior Indebtedness shall
forthwith become immediately due and payable upon demand, regardless of the
express maturity thereof.

     The Borrower may make optional prepayments on this note at any time,
provided that no event of default under the Superior Indebtedness and no event
which may become such event of default with notice of lapse of time, or both,
has occurred and is continuing at the time of such payment or would be caused by
such payment, in which case the Borrower shall not make, and the holder of this
note shall not accept, any such optional prepayment.

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     The foregoing provisions are solely for the purpose of defining the
relative rights of the holders of Superior Indebtedness on the one hand, and the
Lender on the other hand, and nothing herein shall impair, as between the
Borrower and the Lender, the obligation of the Borrower which is unconditional
and absolute, to pay the principal, premium, if any, and interest on this note
in accordance with its terms, nor shall anything herein prevent the Lender from
exercising all remedies otherwise permitted by applicable law or hereunder upon
default hereunder, subject to the rights of the holders of Superior Indebtedness
as herein provided.

     This note is subject to further terms and conditions specified in the
Subordination Agreement executed among the Lender and The First National Bank of
Chicago, as Agent under the Credit Agreement dated as of the date hereof (as
amended or modified from time to time, the "Subordination Agreement"), and if
there is any conflict between the terms and provisions of this note and the
Subordination Agreement that terms and provisions of the Subordination Agreement
shall control.

     This note supercedes and replaces in its entirety the note dated January 7,
1998 in the amount of $56,411,000 payable by Borrower to Lender.

     This note shall be governed by, and interpreted and construed in accordance
with, the laws of the State of Michigan.

                                       CMS OIL AND GAS COMPANY

                                       By:  /s/ William H. Stephens III
                                          --------------------------------------

                                      Its: Executive Vice President,
                                           General Counsel & Secretary
                                          --------------------------------------

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                                                                EXHIBIT 10.8

                                      NOTE
                                                                October 10, 2000
US$32,515,200

     SECTION 1. AMOUNT; INTEREST; PAYMENTS; DEFAULT. Western Australia Gas
Transmission Company I, a Cayman Islands corporation, (together with its
successors and permitted assigns, "Borrower"), for value received, hereby
promises to pay to CMS Oil and Gas (International) Ltd., a Cayman Islands
corporation ("Holder"), the principal amount of Thirty-two Million Five Hundred
Fifteen Thousand Two Hundred United States Dollars (US$32,515,200). Such payment
shall be made on January 8, 2001 (the "Maturity Date").

     The Borrower further agrees to pay, in lawful money of the United States of
America ("Dollars") and in immediately available funds, interest from the date
hereof on the unpaid and outstanding principal amount hereof until such unpaid
and outstanding principal amount shall become due and payable (whether at the
Maturity Date, by acceleration or otherwise) in arrears on the Maturity Date at
a rate per annum equal to 6.44% (the "Borrowing Rate"). All accruals of interest
shall be calculated on the basis of a 360-day year and the actual number of days
elapsed, including the date on which each payment of interest is made. If any
amounts required to be paid by the Borrower under this Note remain unpaid at the
Maturity Date, interest shall accrue on the aggregate outstanding balance of
such unpaid amount from the Maturity Date until those amounts are paid in full
at a rate per annum equal to the Borrowing Rate plus 200 basis points (2%).

     The Borrower has the right to prepay the principal and interest, or a
portion thereof, without penalty, at any time prior to the Maturity Date. The
Borrower may, on any date (the "Prepayment Date") on no less than one (1)
Business Day's (as defined hereinafter) prior written notice (each a "Prepayment
Notice"), prepay all or any portion of the then outstanding principal balance of
the Note specified in such Prepayment Notice, by paying to the Holder on such
date the principal amount specified in such Prepayment Notice, together with all
accrued but unpaid interest on such principal amount so prepaid on and as of the
date of such prepayment. Any amount prepaid may not be reborrowed hereunder.

     On the Maturity Date, the Borrower shall pay or cause to be paid to the
Holder the aggregate outstanding principal amount of the Note, all accrued but
unpaid interest thereon and all other amounts then due under this Note.

     All payments on or in respect of this Note shall be made by wire transfer
of immediately available funds, with the Federal Reference number relating to
such transfer received by Holder no later than 12:00 p.m. New York time, to such
account as may be specified in writing by Holder from time to time. If any
payment cannot be made via wire transfer, such payment shall be made by check
(drawn off a U.S. bank branch) made payable to CMS Oil and Gas (International)
Ltd., Fairlane Plaza South, 330 Town Center Drive, Suite 1100, Dearborn
Michigan, 48126, USA. Any payment

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or prepayment received by the Holder after 12:00 noon New York time, shall be
deemed to have been received on the next succeeding Business Day. If any payment
on this Note becomes due and payable on a date that is not a Business Day,
"Business Day" being a day that is not a Saturday, Sunday or legal holiday in
the State of Michigan, the Cayman Islands, or Western Australia, or a day on
which banking institutions chartered by the State of Michigan, the Cayman
Islands, or Australia are legally required or authorized to close, such payment
shall be made on the first succeeding Business Day.

     All payments under this Note shall be applied, to the extent of the amount
thereof, first, to any costs, charges or expenses then due and payable by the
Borrower to the Holder hereunder, second, to the amount of accrued but unpaid
interest on the Note as of the date of such payment or with respect to any
prepayment, to the amount of all accrued but unpaid interest on the principal
amount so prepaid, and third, against the outstanding principal balance of the
Note as of the date of such payment.

     All payments or prepayments under this Note shall not be subject to set-off
or counterclaim of any kind for any amounts which may be due or alleged to be
due from the Holder to the Borrower.

     If any of the following events (each an "Event of Default") shall occur and
be continuing after the applicable grace period and notice requirement (if any),
the Holder shall be entitled to exercise the remedies set forth herein:

     (a) the Borrower shall fail to make payment when due and payable of any
amount that the Borrower is obligated to pay under this Note;

     (b) (i) the Borrower shall generally not pay its debts as such debts become
due, or shall admit in writing its inability to pay its debts generally, or
shall make an assignment for the benefit of creditors; or (ii) any proceeding
shall be instituted by or against the Borrower seeking to adjudicate it as
bankrupt or insolvent, or seeking liquidation, winding up, reorganization,
arrangement, adjustment, protection, relief, or composition of its debts under
any law relating to bankruptcy, insolvency, or reorganization or relief of
debtors, or seeking the entry of an order for relief or the appointment of a
receiver, trustee, or other similar official for it or for any substantial part
of its property and, in the case of a proceeding instituted against the
Borrower, either such proceeding shall remain undismissed or unstayed for a
period of 60 days or any of the actions sought in such proceeding (including,
without limitation, the entry of an order for relief against the Borrower or the
appointment of a receiver, trustee, custodian or other similar official for the
Borrower or any of its property) shall occur; or (iii) the Borrower shall take
any corporate or other action to authorize any of the actions set forth above in
this subsection (b); or

     (c) one or more judgments, decrees or orders for the payment of money in
excess of $5 Million in the aggregate shall be rendered against the Borrower or
its properties and either (i) enforcement proceedings shall have been commenced
by any creditor upon any such judgment or

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order or (ii) there shall be any period of 30 consecutive days during which a
stay of enforcement of such judgment or order, by reason of a pending appeal or
otherwise, shall not be in effect; or

     (d) any material provision of this Note, after execution hereof shall for
any reason other than the express terms hereof cease to be valid and binding on
any party hereto; or the Borrower, or any court or governmental regulatory body
having jurisdiction over the Borrower, shall so assert in writing; or

     (e) any government or governmental authority shall have condemned,
nationalized seized, or otherwise expropriated all or any substantial part of
the property or other assets of the Borrower or of its capital stock or shall
have assumed custody or control of such property or other assets or of the
business or operations of the Borrower or of its capital stock or shall have
taken any action for the dissolution, receivership or disestablishment of the
Borrower or any action that would prevent the Borrower or its officers from
carrying on its business or operations or a substantial part thereof; or

     (f) any material adverse change in the financial condition or business of
the Borrower shall occur, which, in the reasonable opinion of the Holder, may
imperil, delay, or prevent the fulfillment by the Borrower of any of its
obligations under this Note.

     Upon the occurrence of any one or more Events of Default, all amounts then
remaining unpaid on this Note may become or be declared to be immediately due
and payable as provided in and subject to the limitations specified in this
Note. Borrower hereby waives presentment, demand, notice, protest, notice of
nonpayment, notice of protest, and all other notices, demands or conditions
precedent of any kind in connection with the delivery, acceptance, performance,
collection and/or enforcement of this Note.

     SECTION 2. PAYMENT IN OTHER CURRENCY. Notwithstanding the above stated
terms, if Borrower is unable to purchase Dollars or unable to transfer the
Dollars so purchased in order to make any payments as required hereunder by
reason of restrictions imposed by law, then the obligation of the Borrower in
respect of any sum due from it to the Holder hereunder shall be discharged only
to the extent that on the Business Day following receipt by the Holder of any
sum in currency other Dollars, the Holder may purchase Dollars with such other
currency after any premiums and costs of exchange. If the Dollars so purchased
by the Holder are less than the sum originally due to the Holder in Dollars, the
Borrower agrees, as a separate and independent obligation and notwithstanding
any such payment, to indemnify the Holder against such loss. The Borrower shall
pay for its own account, and indemnify, defend and hold the Holder harmless
from, any claim or liability which it may incur by reason of any tax or other
cost of any nature incurred in connection with any such payment under this
Section 2.

     SECTION 3. TAXES. (a) All payments by the Borrower hereunder shall be made
free and clear of and without deduction for and on account of any and all
present or future taxes, levies,

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imposts, deductions, charges, fees or withholdings, and all liabilities with
respect thereto, including but not limited to taxes on the interest income or
receipts of the Holder of this Note, imposed by the laws or taxing authorities
of any jurisdiction, but excluding taxes on the overall income of the Holder
("Taxes"), all of which shall be for the account of the Borrower. If the
Borrower shall be required by law to make any deduction or withholding with
respect of taxes from or in respect of any sum payable hereunder to the Holder
(i) the sum payable shall be increased as may be necessary so that after making
all required deductions or withholdings (including deductions or withholdings
applicable to additional sums payable under this Section 3(a)) the Holder
receives an amount equal to the sum it would have received had no such
deductions or withholdings been made, (ii) the Borrower shall make such
deductions or withholdings and (iii) the Borrower shall pay the full amount
deducted or withheld to the relevant taxation authority or other authority in
accordance with applicable law.

           (b) In addition, the Borrower agrees to pay any present or future
stamp or documentary taxes or any other excise or property taxes, charges or
similar levies that arise from any payment made hereunder or from the execution,
delivery or registration of this Note, or otherwise with respect to, this Note,
excluding taxes, charges or similar levies on income of the Holder under this
Note ("Other Taxes).

           (c) The Borrower will indemnify the Holder for the full amount of
Taxes and Other Taxes, (including, without limitation, any Taxes and any Other
Taxes imposed by any jurisdiction on amounts payable under this Section 3) paid
by the Holder and any liability (including penalties, interest and expenses)
arising therefrom or with respect thereto, whether or not such Taxes or Other
Taxes were correctly or legally asserted. Reimbursement under this
indemnification shall be made within 30 days from the date the Holder makes
written demand therefor; provided, that the Holder shall not be entitled to
demand payment under these provisions for any amount if such demand is not made
within one year following the date upon which the Holder shall have been
required to pay such amount.

     SECTION 4. COSTS, EXPENSES AND INDEMNIFICATION. (a) The Borrower agrees to
(i) reimburse on demand all reasonable costs and expenses of the Holder
(including, without limitation, reasonable fees and expenses of counsel to the
Holder) in connection with (A) the preparation, negotiation, execution and
delivery of this Note and (B) any proposed modification, amendment or consent
relating to this Note, and (ii) to pay on demand all reasonable costs and
expenses of the Holder, and on and after the date upon which this Note becomes
or is declared to be due and payable or an Event of Default shall have occurred
and be continuing, the Holder (including, without limitation, reasonable fees
and expenses of counsel to the Holder and, from and after such date, counsel for
the Holder (including the allocated costs and expenses of in-house counsel)) in
connection with the enforcement (whether through negotiations, legal proceedings
or otherwise) of this Note.

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           (b) The Borrower further agrees to indemnify and hold the Holder and
its respective officers, directors, employees, professional advisors and
affiliates (each, an "Indemnified Person") harmless from and against any and all
claims, damages, losses, liabilities, costs or expenses (including reasonable
attorney's fees and expenses, whether or not such Indemnified Person is named as
a party to any proceeding or is otherwise subjected to judicial or legal process
arising from any such proceeding) that any of them may incur or that may be
claimed against any of them by any person by reason of or in connection with the
execution, delivery or performance of this Note or any transaction contemplated
hereby, or the use by the Borrower of the proceeds of the Note; or in connection
with any documentary taxes, assessments or charges made by any governmental
authority by reason of the execution and delivery of this Note; provided however
that nothing contained in this subsection (b) shall constitute a relinquishment
or waiver of the Borrower's rights to any independent claim that the Borrower
may have against any Indemnified Person for such Indemnified Person's gross
negligence or willful misconduct.

           (c) The Borrower's obligations under this Section 4 shall survive the
repayment of all amounts owing to the Holder under the Note. If and to the
extent that the obligations of the Borrower under this Section 4 are
unenforceable for any reason, the Borrower agrees to make the maximum
contribution to the payment and satisfaction thereof that is permissible under
applicable law.

     SECTION 5. INCREASED COSTS. If as result of any legal rule or of any
resolution of any authority the Holder determines that the cost to it of making
or maintaining this Note is increased or any amount received or receivable by
the Holder is reduced, then the Borrower will immediately pay to the Holder any
additional amount(s) that the Holder determines will compensate it for the
effect of such increased cost, or reduction in amount, plus lost profits.

     SECTION 6. NO WAIVER OF REMEDIES. No failure on the part of the Holder to
exercise, and no delay in exercising, any right under this Note shall operate as
a waiver thereof; nor shall any single or partial exercise of any such right
preclude any other or further exercise thereof or the exercise of any other
right. The remedies herein provided are cumulative and not exclusive of any
remedies provided by law.

     SECTION 7. SEVERABILITY. If any provision, term or condition of this Note
or the application thereof to any person or circumstance shall for any reason be
held illegal, invalid or unenforceable, then the same shall not adversely affect
or impair the validity and enforceability of the other provisions, terms and
conditions hereof nor the application of any such provisions, terms and
conditions to any other person or in any other circumstance.

     SECTION 8. HEADINGS DESCRIPTIVE, ETC. The headings of the several sections
and subsections of this Note are inserted for convenience only and shall not in
any way affect the meaning or construction of any provision of this Note.

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     SECTION 9. ASSIGNMENTS. Holder shall not sell, assign, transfer, negotiate
or otherwise dispose of all or a portion of its interest in this Note to any
other person unless such person is a shareholder of Borrower.

     SECTION 10. GOVERNING LAW AND JURISDICTION PROVISION. This Note shall be
governed by, and interpreted and construed in accordance with, the laws of the
State of Michigan of the United States of America.

     IN WITNESS WHEREOF, Borrower has caused this Note to be duly executed as of
the date first above written.

                                    Western Australia Gas Transmission Company I

                                    By:  /s/ William J. Haener
                                       ----------------------------------

                                    Name:  William J. Haener
                                         --------------------------------

                                    Title:  President
                                          -------------------------------

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