EXHIBIT 10.21


THE SECURITIES REPRESENTED HEREBY HAVE NOT BEEN REGISTERED UNDER THE SECURITIES
ACT  OF  1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS.  THE SECURITIES
MAY NOT BE  OFFERED  FOR SALE, SOLD, TRANSFERRED OR ASSIGNED (I) IN THE ABSENCE
OF  (A)  AN EFFECTIVE REGISTRATION  STATEMENT  FOR  THE  SECURITIES  UNDER  THE
SECURITIES  ACT OF 1933, AS AMENDED, OR APPLICABLE STATE SECURITIES LAWS OR (B)
AN OPINION OF COUNSEL, IN A GENERALLY ACCEPTABLE FORM, THAT REGISTRATION IS NOT
REQUIRED UNDER SAID ACT OR APPLICABLE STATE SECURITIES LAWS OR (II) UNLESS SOLD
PURSUANT TO RULE  144  UNDER  SAID  ACT.   NOTWITHSTANDING  THE  FOREGOING, THE
SECURITIES  MAY  BE  PLEDGED  IN CONNECTION WITH A BONA FIDE MARGIN ACCOUNT  OR
OTHER LOAN OR FINANCING ARRANGEMENT  SECURED BY THE SECURITIES.  ANY TRANSFEREE
OF THIS NOTE SHOULD CAREFULLY REVIEW THE  TERMS OF THIS NOTE, INCLUDING SECTION
4 HEREOF.  THE PRINCIPAL AMOUNT REPRESENTED  BY  THIS NOTE MAY BE LESS THAN THE
AMOUNTS SET FORTH ON THE FACE HEREOF PURSUANT TO SECTION 4 HEREOF.


                                 SENIOR  NOTE


Original Issuance Date:January 31, 2007
Amendment and Restatement Date:April 1, 2008

Note No.:  NVAM -001                                             $17,908,013.11

FOR  VALUE  RECEIVED,  SOUTH  TEXAS  OIL  COMPANY,  a Nevada  corporation  (the
"COMPANY"),  hereby promises to pay to The Longview Fund,  L.P.,  a  California
limited partnership,  or  its  registered  assigns (the "HOLDER") the principal
amount of Seventeen Million Nine Hundred Eight  Thousand  Thirteen  and  11/100
United  States  Dollars  ($17,908,013.11) (the "INITIAL PRINCIPAL AMOUNT") when
due, whether upon maturity,  acceleration,  redemption or otherwise, and to pay
interest ("INTEREST") on the unpaid principal  balance  hereof on each Interest
Payment Date (as defined in the Appendix hereto) and upon  maturity, or earlier
upon  acceleration or prepayment pursuant to the terms hereof,  (i)  from  (and
including)  the Original Issuance Date to (but not including) the Amendment and
Restatement Date  at  the  Original  Interest  Rate (as defined in the Appendix
hereto),  and  (ii)  from (and including) the Amendment  and  Restatement  Date
through and including  the  Maturity  Date  at the Applicable Interest Rate (as
defined in the Appendix hereto).  Interest on  this  Note  is  payable  on each
Interest  Payment  Date and on the Maturity Date, if applicable, or if earlier,
upon acceleration or redemption pursuant to the terms hereof, and such Interest
shall accrue from and  after  the  Issuance  Date  (as  defined in the Appendix
hereto) and shall be computed on the basis of a 365-day year  and  actual  days
elapsed.   Interest  shall  be payable in cash in accordance with the foregoing
sentence and Section 5.

This Note is being issued in  connection with the Securities Purchase Agreement
(as defined in the Appendix hereto),  pursuant  to  which,  among other things,
each  of  the  Company,  the Holder and Longview Marquis Master Fund,  L.P.,  a
British Virgin Islands limited  partnership  (together  with  the  Holder,  the
"HOLDERS")  agreed  to  amend  and  restate that certain Revolving Credit Note,
dated January 31, 2007, in an original  aggregate  amount  of  Fifteen  Million
Dollars  ($15,000,000.00),  which  Revolving  Credit Note was first amended and
restated as set forth in that certain First Amendment  to  Loan  Agreement  and
Revolving  Credit  Note,  dated  September  25,  2007  (the "FIRST AMENDMENT"),
pursuant to which the principal amount was increased to  Thirty Million Dollars
($30,000,000)  (such Revolving Credit Note as amended by the  First  Amendment,
the "REVOLVING NOTE").

      (1)   Certain   Defined  Terms.   Each  capitalized  term  used  and  not
otherwise defined in this  Note shall have the meaning ascribed to such term in
the Appendix hereto (or incorporated  by reference therein), and the meaning of
each such term is incorporated herein by this reference.

      (2)   Payments of Principal and Interest.   All  payments under this Note
shall be made in lawful money of the United States of America  by wire transfer
of immediately available funds to such account as the Holder may  from  time to
time  designate  by  written  notice  to  the  Company  in  accordance with the
provisions of this Note.  Interest shall be paid quarterly in  arrears  on each
Interest  Payment  Date  and on the Maturity Date.  Any amount that is not paid
when due shall bear interest  at  the Default Rate from the date such amount is
initially due until the same is paid in full.  Whenever any amount expressed to
be due by the terms of this Note is  due on any day that is not a Business Day,
the same shall be due instead on the next  succeeding Business Day and interest
thereon shall be payable at the Applicable Interest Rate.

      (3)   Principal Payments.

            (a)   On the Maturity Date.  If  any  Principal remains outstanding
on the Maturity Date, then the Holder shall surrender  this Note, duly endorsed
for cancellation to the Company, and such Principal shall  be  redeemed  by the
Company  as of the Maturity Date by payment on the Maturity Date, respectively,
to the Holder,  by  wire  transfer of immediately available funds, of an amount
equal to such Principal and  the  related  Interest  Amount,  together with all
other amounts payable under this Note or the Securities Purchase Agreement.

            (b)   Optional Early Redemption by Company.

                  (i)   General.  At any time, and from time to time, after the
      Issuance Date, the Company shall have the right to redeem  some or all of
      the Principal (a "COMPANY EARLY REDEMPTION") by delivering to  the Holder
      written notice (the "COMPANY EARLY REDEMPTION NOTICE") at least  five (5)
      Business  Days prior to the date selected by the Company for such Company
      Early Redemption.  Any Company Early Redemption shall be for an amount in
      cash equal  to  the  sum  of  (such  sum, the "AGGREGATE EARLY REDEMPTION
      AMOUNT"):

                        (A)   the Principal  then being redeemed and prepaid by
            the Company on the Company Early Redemption Date (as defined below)
            pursuant  to  this Section 3(b) (the  "EARLY  REDEMPTION  PRINCIPAL
            AMOUNT");

                        (B)   the  Interest  Amount  with respect to such Early
            Redemption  Principal Amount as of the applicable  prepayment  date
            (the "EARLY REDEMPTION INTEREST AMOUNT" and together with any Early
            Redemption Principal  Amount,  the  "EARLY REDEMPTION PRINCIPAL AND
            INTEREST  AMOUNT"),  which date shall be  the  date  on  which  the
            Company Early Redemption  will occur (the "COMPANY EARLY REDEMPTION
            DATE"); and

                        (C)   the Redemption  Premium with respect to the Early
            Redemption  Principal  Amount as of the  Company  Early  Redemption
            Date.

                        The Company Early Redemption Notice shall state:

                        (D)   the Company Early Redemption Date;

                        (E)   the Aggregate Early Redemption Amount; and

                        (F)   that the  Company is simultaneously redeeming the
            same percentage of the outstanding  principal balance of each Other
            Note of the same Series as this Note.

      For purposes hereof, any Notes having the same  Issuance  Date  shall  be
      deemed to be the same "SERIES").  A Company Early Redemption Notice shall
      be  irrevocable  by  the  Company.  The failure of the Company to pay the
      Aggregate Early Redemption Amount in full on the Company Early Redemption
      Date stated in such notice  shall  constitute  an  Event  of Default. Any
      portion of the Aggregate Early Redemption Amount not paid on  the Company
      Early Redemption Date shall bear interest at the Default Rate until  paid
      in full.

                  (ii)  Mechanics  of Company Early Redemption.  If the Company
      has  delivered  a Company Early  Redemption  Notice  in  accordance  with
      Section 3(b)(i),  then, on the Company Early Redemption Date, the Company
      shall pay the Aggregate  Early Redemption Amount in cash by wire transfer
      of immediately available funds  to  an  account designated by the Holder.
      Notwithstanding  anything  contained herein  to  the  contrary,  (A)  the
      Company  shall not effect any  Company  Early  Redemption  unless  it  is
      simultaneously redeeming the same percentage of the outstanding principal
      balance of  each  Other  Note of the same Series as this Note, and (B) no
      Company Early Redemption Notice  shall  contain  any  material non-public
      information regarding the Company or any of the Subsidiaries.

      (1)   Surrender  of Note.  Notwithstanding anything to the  contrary  set
forth in this Note, upon  any  redemption  of  the  Principal  of  this Note in
accordance  with  the  terms  hereof,  the  Holder  shall  not  be  required to
physically  surrender  this Note to the Company unless all of the Principal  is
being repaid and the related  Interest Amount and all other obligations payable
under this Note (including any  other  amounts  due  under this Note) have been
paid in full.  The  Register (as defined in Section 14  hereof)  shall show the
principal  amount redeemed and the date(s) of such redemptions, so  as  not  to
require physical  surrender  of this Note upon each such redemption  The Holder
and any assignee, by acceptance  of  this  Note, acknowledge and agree that, by
reason of the provisions of this paragraph, following redemption of any portion
of this Note, the Principal may be less than the principal amount stated on the
face hereof.

      (2)   Interest.   Interest  shall be payable  by  the  Company,  on  each
Interest Payment Date and at the Maturity  Date,  to  the record Holder of this
Note  on such Interest Payment Date by wire transfer of  immediately  available
funds.  Any  accrued  and  unpaid  Interest  which is not paid within three (3)
Business Days of such accrued and unpaid Interest's Interest Payment Date shall
bear interest at the Default Rate from such Interest  Payment  Date  until  the
same is paid in full.

      (3)   Voting  Rights.   The  holders  of  the  Notes shall have no voting
rights, except as required by law and as expressly provided in this Note.

      (4)   Defaults and Remedies.

            (a)   Events of Default.  An "EVENT OF DEFAULT" means:

                        (i)   Any default in payment of  (A)  any  Principal on
            any of the Notes or (B) any Aggregate Early Redemption Amount, when
            and as due;

                        (ii)  Any default in payment of any Interest  Amount or
            any other amount due that is not included in an amount described in
            the  immediately preceding clause (i) and that is not cured  within
            three (3) Business Days from the date such Interest Amount or other
            amount was due;

                        (iii) Any  failure  by the Company, for a period of ten
            (10) consecutive days (after giving  effect to any grace period set
            forth  in the Securities Purchase Agreement  or  other  Transaction
            Document  relating  to  any  such breach), to comply with any other
            provision of this Note in all material respects;

                        (iv)  Any default  in  payment  of  at  least $250,000,
            individually  or in the aggregate, under or acceleration  prior  to
            maturity of, or  any  event or circumstances arising, such that any
            Person is entitled, or  could,  with  the  giving  of notice and/or
            lapse  of time and/or the fulfillment of any condition  and/or  the
            making of  any determination, become entitled, to require repayment
            before its stated  maturity  of, or to take any step to enforce any
            security for, any mortgage, indenture  or  instrument  under  which
            there  may  be issued or by which there may be secured or evidenced
            any indebtedness  for  money  borrowed  of at least $250,000 by the
            Company  or  any of the Subsidiaries, or for  money  borrowed,  the
            repayment of at  least  $250,000  of  which  is  guaranteed  by the
            Company  or  any of the Subsidiaries, whether such indebtedness  or
            guarantee now exists or shall be created hereafter;

                        (v)   The  Company  or any of the Subsidiaries pursuant
            to or within the meaning of any Bankruptcy  Law:  (A)  commences  a
            voluntary  case  or  applies for a receiving order; (B) consents to
            the entry of an order  for relief against it in an involuntary case
            or consents to any involuntary  application  for a receiving order;
            (C) consents to the appointment of a Custodian  of it or any of the
            Subsidiaries  for  all  or substantially all of its  property;  (D)
            makes a general assignment  for  the  benefit of its creditors; (E)
            admits in writing that it is generally  unable  to pay its debts as
            the  same become due; or (F) takes any action for  the  purpose  of
            effecting any of the foregoing;

                        (vi)  An   involuntary  case  or  other  proceeding  is
            commenced directly against  the  Company or any of the Subsidiaries
            seeking liquidation, reorganization or other relief with respect to
            it or its Indebtedness under any Bankruptcy Law now or hereafter in
            effect  or  seeking  the  appointment   of   a  trustee,  receiver,
            liquidator,  custodian  or  other similar official  of  it  or  any
            substantial part of its property,  and  such  involuntary  case  or
            other  Bankruptcy  Law  proceeding remains undismissed and unstayed
            for a period of thirty (30)  days, or an order of relief is entered
            against the Company or any of  the Subsidiaries as debtor under the
            Bankruptcy Laws as are now or hereafter in effect;

                        (vii) The Company or  any of the Subsidiaries that is a
            party thereto breaches any covenant  or  other term or condition of
            the Security Documents (after giving effect to any grace period set
            forth in such Security Documents relating to any such breach);

                        (viii)The Company or any of the  Subsidiaries  breaches
            any  covenant or other term or condition of the Securities Purchase
            Agreement,  or  any  other  Transaction  Documents (other than this
            Note, or any of the Security Documents or  Section  2, Section 5(t)
            or Section 6 of the Securities Purchase Agreement); provided,  that
            in the case of a breach of a covenant or other term that is curable
            and  would  not  otherwise constitute an Event of Default under any
            other subparagraph  of this Section 7(a), such breach continues for
            ten (10) or more consecutive days without being cured (after giving
            effect to any grace period  set  forth  in  the Securities Purchase
            Agreement  or  other  Transaction  Document relating  to  any  such
            breach);

                        (ix)  The  Company  breaches,  or  otherwise  does  not
            comply with, any of the provisions  of  Section  2, Section 5(t) or
            Section  6  of  the  Securities Purchase Agreement, including,  the
            Company's failure to deliver  an  Officer's Certificate pursuant to
            Section 6(t)(ii) of the Securities  Purchase  Agreement within five
            (5) days of the date such Officer's Certificate  is  required to be
            delivered  pursuant  to Section 6(t)(ii) thereof, or any  Officer's
            Certificate delivered  to  the  Holder  does not contain any of the
            information  required to be included therein  pursuant  to  Section
            6(t)(ii) of the  Securities  Purchase  Agreement,  or  any  of  the
            information contained in any Officer's Certificate delivered to the
            Holder is not true, correct and complete in all material respects;

                        (x)   The  breach  by  the  Company of the terms of any
            subordination  agreement to which it is a  party  relating  to  the
            subordination of any Indebtedness to this Note;

                        (xi)  One  or  more judgments, non-interlocutory orders
            or decrees shall be entered by a U.S. state or federal or a foreign
            court or administrative agency  of  competent  jurisdiction against
            the  Company  and/or  any  of  the Subsidiaries involving,  in  the
            aggregate,  a  liability as to any  single  or  related  series  of
            transactions, incidents or conditions, of $250,000 or more, and the
            same shall remain  unsatisfied,  unvacated,  unbonded  or unstayed,
            pending  appeal  for  a period of thirty (30) days after the  entry
            thereof;

                        (xii) There shall occur a Change of Control;

                        (xiii)There  shall  occur  a  Financial  Covenant  Test
            Failure;

                        (xiv) Any  representation,  warranty,  certification or
            statement  made  by the Company or any of the Subsidiaries  in  the
            Securities Purchase Agreement, this Note, the Security Documents or
            any other Transaction  Documents  or  in  any certificate delivered
            pursuant  to  any  such Transaction Document is  incorrect  in  any
            material respect when made (or deemed made);

                        (xv)  Any Lien created by any of the Security Documents
            shall  at  any time fail  to  constitute  a  valid  first  priority
            perfected Lien  on  all  of  the Collateral purported to be secured
            thereby;

                        (xvi) Any change in  the  condition  or  affairs of the
            Company  or  the Subsidiaries (financial or otherwise) which  would
            have a Material Adverse Effect; or

                        (xvii)The  Company  fails  to file, or is determined to
            have  failed to file, in a timely manner  any  Periodic  Report  or
            Current Report (other than a Current Report that is required solely
            pursuant  to  Item  1.01,  1.02, 2.03, 2.04, 2.05, 2.06, 4.02(a) or
            5.02(e) of Form 8-K as in effect  on the Issuance Date) required to
            be filed with the SEC pursuant to the  1934  Act,  or  the  Company
            fails to disclose the Daily Barrel Average for the calendar quarter
            covered  by  such  Periodic  Report  (or,  in the case of an Annual
            Report on Form 10-K, for the Company's fourth  fiscal  quarter)  or
            such  Periodic  Report  is  not  true,  correct and complete in all
            material respects.

Within two (2) Business Days after the occurrence of  any Event of Default, the
Company   shall   deliver   written   notice   thereof   to  the  Holder   and,
contemporaneously, Publicly Disclose such occurrence and the remedies available
to the holders of the Notes.

            (b)   Remedies.  If an Event of Default occurs  and  is continuing,
the  Holder  may  declare  all  of  this  Note,  including  all amounts payable
hereunder  (the  "ACCELERATION  AMOUNT"),  to  be due and payable  immediately,
except that in the case of an Event of Default arising from events described in
clauses  (v)  and  (vi) of Section 7(a) above, all  amounts  payable  hereunder
immediately shall become  due and payable without further action or notice.  In
addition to any remedy the  Holder  may  have  under  this  Note,  the Security
Documents  and the other Transaction Documents, such unpaid amounts shall  bear
interest at  the  Default  Rate,  and  any  payment  of  Principal prior to the
scheduled maturity thereof as a result of acceleration under  this Section 7(b)
shall be accompanied by the Redemption Premium in respect thereof.   Nothing in
this  Section  7  shall  limit any other rights the Holder may have under  this
Note, the Security Documents or the other Transaction Documents.

      (1)   Vote to Change  the Terms of the Notes.  The written consent of the
Company and the Holders representing at least a majority of the Aggregate Notes
Principal Balance shall be required in order to affect any amendment, waiver or
other modification of any of  the Notes, and upon receipt of such consent, each
Note shall be amended thereby; provided, however, that no change may be made to
the Principal, Applicable Interest  Rate,  or Maturity Date of any Note without
the consent of the Holder thereof.

      (2)   Lost or Stolen Notes.  Upon receipt  by  the  Company  of  evidence
reasonably  satisfactory  to  the  Company  of  the loss, theft, destruction or
mutilation of this Note, and, in the case of loss,  theft or destruction, of an
indemnification undertaking by the Holder to the Company  in customary form and
reasonably  satisfactory  to the Company and, in the case of  mutilation,  upon
surrender and cancellation  of this Note, the Company shall execute and deliver
a replacement Note of like tenor and date.

      (3)   Remedies,  Characterizations,   Other   Obligations,  Breaches  and
Injunctive Relief.  The remedies provided in this Note  shall be cumulative and
in  addition  to  all  other  remedies available under the Securities  Purchase
Agreement, the Security Documents  and  the other Transaction Documents, at law
or  in  equity  (including  a  decree  of  specific  performance  and/or  other
injunctive relief), and no remedy contained  herein shall be deemed a waiver of
compliance with the provisions giving rise to  such  remedy, and nothing herein
shall limit the Holder's right to pursue actual damages  for any failure by the
Company to comply with the terms of this Note.  The Company  covenants  to  the
Holder that there shall be no characterization concerning this instrument other
than  as  expressly  provided herein.  Amounts set forth or provided for herein
with respect to payments  and  the  like (and the computation thereof) shall be
the amounts to be received by the Holder  and  shall  not,  except as expressly
provided  herein,  be  subject to any other obligation of the Company  (or  the
performance thereof).  The  Company  acknowledges  that  a  breach by it of its
obligations hereunder will cause irreparable harm to the Holder  and  that  the
remedy  at  law  for  any such breach may be inadequate.  The Company therefore
agrees that, in the event  of  any such breach or threatened breach, the Holder
shall  be  entitled,  in  addition to  all  other  available  remedies,  to  an
injunction restraining any  breach,  without  the necessity of showing economic
loss and without any bond or other security being required.

      (4)   Specific  Shall  Not  Limit  General;  Construction.   No  specific
provision  contained  in  this  Note  shall limit or modify  any  more  general
provision contained herein.  This Note shall be deemed to be jointly drafted by
the Company and the Holders pursuant to  the  Securities Purchase Agreement and
shall not be construed against any person as the drafter hereof.

      (5)   Failure or Indulgence Not Waiver.   No failure or delay on the part
of the Holder in the exercise of any power, right  or privilege hereunder shall
operate as a waiver thereof, nor shall any single or  partial  exercise  of any
such power, right or privilege preclude other or further exercise thereof or of
any other right, power or privilege.

      (6)   Notice.   Whenever  notice is required to be given under this Note,
unless  otherwise provided herein,  such  notice  shall  be  given  and  deemed
received in accordance with Section 12(f) of the Securities Purchase Agreement.

      (7)   Transfer  of this Note and Note Register.  The Holder may assign or
transfer some or all of  its  rights  hereunder, subject to compliance with the
provisions of Section 3(f) of the Securities  Purchase  Agreement,  without the
consent  of  the  Company.   The  Holder  shall promptly provide notice to  the
Company of the name and address of the assignee or transferee and the Principal
Amount  of  Notes assigned or transferred, as  applicable.  The  Company  shall
maintain, at  one  of  its  offices  in  the  United States, a register for the
recordation of the names and addresses of each  holder  of  the  Notes, and the
principal  amount of the Notes owed to each such holder pursuant to  the  terms
hereof and of  the Other Notes from time to time (the "REGISTER").  The entries
in the Register shall be conclusive absent manifest error, and the Company, the
Collateral Agent  and the Holder shall treat each person whose name is recorded
in the Register pursuant  to  the  terms hereof as the Holder for all purposes,
notwithstanding notice to the contrary.   The  Register  shall be available for
inspection  by  the  Collateral  Agent  and  any  holder of the Notes,  at  any
reasonable time and from time to time upon reasonable  prior notice.  The Notes
are intended to be obligations in "registered form" for  purposes  of  Sections
871  and 881 of the Internal Revenue Code of 1986, as amended, and the Treasury
Regulations  promulgated  thereunder,  and  the provision of this Note shall be
interpreted consistently therewith.  Notwithstanding  anything  to the contrary
contained  in this Section 14, each such assignee or transferee, upon  becoming
the Holder hereunder, acknowledges that it is bound by the terms and conditions
of Section 5.12  of  the Amended and Restated Security Agreement and agrees to,
promptly upon the request  of the Collateral Agent, deliver to Collateral Agent
a written Joinder to the Amended  and  Restated  Security  Agreement  and other
Security Documents.

      (8)   Payment  of  Collection,  Enforcement  and  Other  Costs.   Without
limiting  the  provisions  of  the  Securities Purchase Agreement and the other
Transaction Documents, if (a) this Note  is  placed in the hands of an attorney
for collection or enforcement or is collected  or  enforced  through  any legal
proceeding,  or  (b)  an  attorney  is  retained to represent the Holder in any
bankruptcy, reorganization, receivership  of  the  Company or other proceedings
affecting Company creditors' rights and involving a claim under this Note, then
the  Company shall pay the costs incurred by the Holder  for  such  collection,
enforcement or action, including reasonable attorneys' fees and disbursements.

      (9)   Cancellation.   After  all Principal, Interest and other amounts at
any time owed under this Note have been  paid  in  full  in accordance with the
terms  hereof,  this  Note  shall automatically be deemed canceled  and  deemed
surrendered to the Company for  cancellation.   Additionally,  the Holder shall
deliver  the  original  Note  to the Company, which shall be cancelled  by  the
Company and shall not be reissued.

      (10)  Note  Exchangeable  for   Different   Denominations.    Subject  to
Section 4,  in  the  event  of  a  redemption of less than all of the Principal
pursuant to the terms hereof, the Company shall, upon the request of Holder and
tender of this Note promptly cause to  be issued and delivered to the Holder, a
new Note of like tenor representing the  remaining  Principal that has not been
so repaid.  This Note is exchangeable, upon the surrender  hereof by the Holder
at the principal office of the Company, for a new Note or Notes  containing the
same terms and conditions and representing in the aggregate the Principal,  and
each  such  new  Note  will  represent  such  portion  of  such Principal as is
designated by the Holder at the time of such surrender.

      (11)  Taxes.

            (a)   Payments  Free  of  Taxes.   Any and all payments  by  or  on
account of any obligation of the Company or any  of the Subsidiaries under this
Note, the Securities Purchase Agreement, the Security  Documents  or  any other
Transaction  Document  shall  be  made  without  any  set-off,  counterclaim or
deduction  and  free  and  clear  of  and without deduction for any Indemnified
Taxes;  provided  that if the Company or  any  of  the  Subsidiaries  shall  be
required to deduct any Indemnified Taxes from such payments, then:

                        (i)   The  sum  payable shall be increased as necessary
            so that after making all required  deductions (including deductions
            applicable to additional sums payable  under  this  Section 18(a)),
            the  Holder  receives  an  amount  equal  to the sum it would  have
            received had no such deductions been made;

                        (ii)  The  Company or such Subsidiary,  as  applicable,
            shall make such deductions; and

                        (iii) The Company  or  such Subsidiary shall timely pay
            the full amount deducted to the relevant  Governmental Authority in
            accordance with applicable law.

            (b)   Indemnification by the Company.  The  Company shall indemnify
the Holder, within ten (10) days after written demand therefor,  for  the  full
amount of any Indemnified Taxes imposed upon the Holder, on or with respect  to
any  payment  by  or  on account of any obligation of the Company or any of the
Subsidiaries under any  of  the  Notes,  the Securities Purchase Agreement, the
Security Documents and the other Transaction  Documents  (including Indemnified
Taxes  imposed  or  asserted on or attributable to amounts payable  under  this
Section  18)  and  any penalties,  interest  and  reasonable  expenses  arising
therefrom or with respect  thereto,  whether or not such Indemnified Taxes were
correctly  or  legally  imposed  or  asserted   by  the  relevant  Governmental
Authority.  The Holder shall provide the Company reasonably prompt notification
of the assessment and pay the Indemnified Taxes to  the  Governmental Authority
promptly  following receipt of indemnification therefor from  the  Company.   A
certificate  of  the Holder as to the amount of such payment or liability under
this Section 18 shall  be  delivered  to the Company within one (1) year of the
payment  of Indemnified Taxes by the Holder  and  shall  be  conclusive  absent
manifest error.

            (c)   Refunds.   If  the Holder receives a refund in respect of any
Indemnified Taxes as to which it has  been  indemnified  by the Company or with
respect  to  which  the  Company has paid additional amounts pursuant  to  this
Section 18, it shall, within  thirty  (30)  days from the date of such receipt,
pay  over such refund to the Company (but only  to  the  extent  of  additional
amounts  paid  by  the  Company  under  this  Section  18  with  respect to the
Indemnified  Taxes  giving  rise to the refund), net of all reasonable  out-of-
pocket expenses of the Holder and without interest (other than interest paid by
the relevant Governmental Authority with respect to such refund); provided that
the Company, upon the request  of  the  Holder, agrees to repay the amount paid
over to the Company (plus any penalties,  interest  or other charges imposed by
the relevant Governmental Authority) to the Holder in  the  event the Holder is
required to repay such refund to such Governmental Authority.   This  paragraph
shall not be construed to require the Holder to make available its tax  returns
(or any other information relating to its taxes that it deems confidential)  to
the Company or any other person.

            (d)   Certificates.   A  Holder  that  is  a  U.S.  person for U.S.
federal  income  tax  purposes  will  provide  the  Company  with all clearance
certificates and completed and executed Internal Revenue Service  Form W-9's or
valid  substitutions  thereof, or similar documents that may be required  under
applicable law to relieve  the  Company of any obligation to withhold or escrow
any portion of the amounts paid under  this Note, reasonably promptly following
the reasonable written request therefor  by  the  Company.   On or prior to the
Issuance Date, a Holder that is not a U.S. person for U.S. federal  income  tax
purposes  will  provide the Company with all appropriate clearance certificates
and completed and  executed  Internal  Revenue  Service  Form  W-8BENs, W-8ECIs
and/or  W-8IMYs,  as  applicable,  or  valid substitutions thereof, or  similar
documents that may be required under applicable  law  to relieve the Company of
any obligation to withhold or escrow any portion of the amounts paid under this
Note.

      (1)   Waiver  of Notice.  To the extent permitted  by  law,  the  Company
hereby waives demand,  notice,  protest  and  all  other demands and notices in
connection with the delivery, acceptance, performance,  default  or enforcement
of this Note, the Security Documents, the Securities Purchase Agreement and the
other Transaction Documents.

      (2)   Governing  Law.   This  Note  shall  be  construed and enforced  in
accordance  with,  and  all  questions  concerning the construction,  validity,
interpretation and performance of this Note  shall be governed by, the internal
laws of the State of New York, without giving  effect  to  any choice of law or
conflict  of  law provision or rule (whether of the State of New  York  or  any
other country or  jurisdiction) that would cause the application of the laws of
any jurisdiction or  country  other  than  the  State  of New York.  Each party
hereby  irrevocably  submits to the exclusive jurisdiction  of  the  state  and
federal courts sitting  in  the City of New York, Borough of Manhattan, for the
adjudication of any dispute hereunder  or  in  connection  herewith or with any
transaction  contemplated  hereby  or discussed herein, and hereby  irrevocably
waives, and agrees not to assert in  any  suit, action or proceeding, any claim
that it is not personally subject to the jurisdiction  of  any such court, that
such suit, action or proceeding is brought in an inconvenient forum or that the
venue  of  such  suit,  action  or proceeding is improper.  Each  party  hereby
irrevocably waives personal service  of  process  and consents to process being
served in any such suit, action or proceeding by mailing a copy thereof to such
party at the address for such notices to it under this  Note  and  agrees  that
such service shall constitute good and sufficient service of process and notice
thereof.   Nothing  contained  herein  shall  be deemed to limit in any way any
right  to serve process in any manner permitted  by  law.   EACH  PARTY  HEREBY
IRREVOCABLY  WAIVES  ANY  RIGHT  IT MAY HAVE, AND AGREES NOT TO REQUEST, A JURY
TRIAL FOR THE ADJUDICATION OF ANY  DISPUTE  HEREUNDER OR IN CONNECTION HEREWITH
OR ARISING OUT OF THIS NOTE OR ANY TRANSACTION CONTEMPLATED HEREBY.

      (3)   Payment Set Aside.  To the extent  that the Company makes a payment
or payments to the Holder hereunder or the Holder  enforces  or  exercises  its
rights  hereunder,  and  such  payment  or  payments  or  the  proceeds of such
enforcement  or  exercise  or  any  part  thereof are subsequently invalidated,
declared to be fraudulent or preferential, set aside, recovered from, disgorged
by or are required to be refunded, repaid or otherwise restored to the Company,
by  a  trustee,  receiver or any other person  under  any  law  (including  any
Bankruptcy Law, U.S.  state  or federal law, the laws of any foreign government
or any political subdivision thereof, common law or equitable cause of action),
then to the extent of any such  restoration  the  obligation  or  part  thereof
originally  intended  to  be  satisfied  shall be revived and continued in full
force and effect as if such payment had not  been  made  or such enforcement or
setoff had not occurred.

      (4)   Interpretative Matters.  Unless the context otherwise requires, (a)
all references to Sections, Schedules, Appendices or Exhibits  are to Sections,
Schedules,  Appendices or Exhibits contained in or attached to this  Note,  (b)
words in the  singular  or  plural include the singular and plural and pronouns
stated in either the masculine, the feminine or neuter gender shall include the
masculine, feminine and neuter,  (c)  the words "hereof," "herein" and words to
similar effect refer to this Note in its  entirety, and (d) the use of the word
"including" in this Note shall be by way of example rather than limitation.

      (5)   Signatures.  In the event that  any  signature  to this Note or any
amendment hereto is delivered by facsimile transmission or by  e-mail  delivery
of  a  ".pdf" format data file, such signature shall create a valid and binding
obligation  of  the  party  executing  (or  on  whose  behalf such signature is
executed)  with  the  same  force  and  effect as if such facsimile  or  ".pdf"
signature page were an original thereof.   Notwithstanding  the  foregoing, the
Company shall be required to deliver an originally executed Note to the Holder.
At  the  request  of  any  party each other party shall promptly re-execute  an
original form of this Note or  any amendment hereto and deliver the same to the
other party.  No party hereto shall  raise the use of a facsimile machine or e-
mail delivery of a ".pdf" format data  file to deliver a signature to this Note
or any amendment hereto or the fact that  such  signature  was  transmitted  or
communicated  through  the  use  of a facsimile machine or e-mail delivery of a
".pdf" format data file as a defense  to  the  formation or enforceability of a
contract, and each party hereto forever waives any such defense.

     [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK; SIGNATURE PAGE FOLLOWS]











<PAGE>
                         SIGNATURE PAGE TO SENIOR NOTE



IN WITNESS WHEREOF, the Company has caused this  Note  to  be  executed  on its
behalf by the undersigned as of the year and date first above written.


                                   SOUTH TEXAS OIL COMPANY,
                                   a Nevada corporation



                                   By:     ___________________________
                                   Name:   Scott Zimmerman
                                   Title:  Chief Executive Officer




60626882








<PAGE>
                                   APPENDIX

                             CERTAIN DEFINED TERMS



      Capitalized terms used and not otherwise defined in this Note shall  have
the  respective  meanings  ascribed  to  such  terms in the Securities Purchase
Agreement,  dated  as  of  April  1, 2008,  pursuant to  which  this  Note  was
originally issued (as such agreement may be amended,  restated, supplemented or
modified  from  time  to  time  as  provided therein, the "SECURITIES  PURCHASE
AGREEMENT").  For purposes of this Note,  the  following  terms  shall have the
following meanings:

      "1934  ACT"  means the U.S. Securities Exchange Act of 1934, as  amended,
and the rules and regulations promulgated thereunder.

      "AGGREGATE  NOTES   PRINCIPAL   BALANCE"   means,   as  of  any  date  of
determination, the aggregate outstanding principal amount of  all  the Notes as
of such date.

      "AMENDMENT AND RESTATEMENT DATE" mean April 1, 2008.

      "APPLICABLE INTEREST RATE" means the Interest Rate, or, for so long as an
Event of Default shall have occurred and be continuing, the Default Rate.

      "BANKRUPTCY  LAW" means Title 11, U.S. Code, or any similar U.S.  federal
or  state  law  or law  of  any  applicable  foreign  government  or  political
subdivision thereof for the relief of debtors.

      "BUSINESS DAY"  means any day other than Saturday, Sunday or other day on
which commercial banks  in  New  York City are authorized or required by law to
remain closed.

      "CHANGE  OF  CONTROL"   means (i)  the  consolidation,  merger  or  other
business combination of the Company with or into another Person (other than (A)
a consolidation, merger or other  business  combination in which holders of the
Company's voting power immediately prior to the  transaction continue after the
transaction to hold, directly or indirectly, a majority  of the combined voting
power of the surviving entity or entities entitled to vote  generally  for  the
election  of  a  majority  of  the  members of the board of directors (or their
equivalent if other than a corporation)  of  such  entity  or  entities, or (B)
pursuant to a migratory merger effected solely for the purpose of  changing the
jurisdiction of incorporation of the Company); (ii) the sale or transfer of all
or  substantially all of the Company's assets (including, for the avoidance  of
doubt,  the  sale of all or substantially all of the assets of the Subsidiaries
in the aggregate);  or (iii) the consummation of a purchase, tender or exchange
offer made to, and accepted  by,  the  holders  of  more than a majority of the
outstanding Common Stock.

      "COLLATERAL AGENT" has the meaning ascribed to  such  term in the Amended
and Restated Security Agreement.

      "CURRENT REPORT" means a current report on Form 8-K under the 1934 Act.

      "CUSTODIAN" means any receiver, trustee, assignee, liquidator  or similar
official under any Bankruptcy Law.

      "DEFAULT RATE" means the percent per annum rate equal to the sum  of  (i)
the Interest Rate plus (ii) 5.00 percent (i.e., 500 basis points).

      "DOLLARS" or "$" means U.S. Dollars.

      "EXCLUDED  TAXES"  means,  with  respect  to  the  Holder,  or  any other
recipient of any payment made or to be made by or on account of any obligations
of  the  Company  or  any  of  the Subsidiaries under the Notes, the Securities
Purchase Agreement or under any other Transaction Document, income or franchise
taxes  imposed  on  (or  measured  by)  such  recipient's  net  income  by  any
jurisdiction under which such recipient  is organized or in which its principal
offices are located.

      "GOVERNMENTAL AUTHORITY" means the government  of  the  United  States of
America  or  any  other  nation,  or any political subdivision thereof, whether
state,  provincial  or  local,  or  any   agency,  authority,  instrumentality,
regulatory  body,  court, central bank or other  entity  exercising  executive,
legislative, judicial, taxing, regulatory or administration powers or functions
of or pertaining to government.

      "INDEMNIFIED TAXES" means taxes other than Excluded Taxes.

      "INTEREST AMOUNT"  means  as  of  any  date,  with  respect to any of the
Principal,  all  accrued  and  unpaid Interest (including any Interest  at  the
Default Rate) on such Principal through and including such date.

      "INTEREST PAYMENT DATE" means  the  first  Business  Day of each calendar
quarter, beginning with the calendar quarter that commences  on  July  1, 2008,
through  and  including  the last calendar quarter that commences prior to  the
Maturity Date.

      "INTEREST RATE" means twelve and one-half percent (12.50%) per annum.

      "ISSUANCE DATE" means January 31, 2007.

      "MATURITY DATE" means December 31, 2009.

      "NOTES" means, collectively,  this Note and all Other Notes issued by the
Company pursuant to the Securities Purchase  Agreement on the Issuance Date and
on  any  Additional  Closing  Date,  and  all  notes   issued  in  exchange  or
substitution therefor or replacement thereof.

      "ORIGINAL  INTEREST RATE" means the "prime rate" published  in  The  Wall
Street Journal from  time  to  time,  plus  four  percent  (4%), which shall be
increased or decreased as the case may be for each increase  or decrease in the
prime rate in an amount equal to such increase or decrease in  the  prime rate;
each  change  to  be  computed  as  of  the first Business Day of each calendar
quarter.  Notwithstanding the foregoing,  the  Original Interest rate shall not
be less than eight percent (8%).

      "OTHER NOTES" means all of the senior notes,  other  than this Note, that
have  been issued by the Company pursuant to the Securities Purchase  Agreement
and all  Notes  issued  in  exchange  or  substitution  therefor or replacement
thereof.

      "PERSON" means an individual, a limited liability company, a partnership,
a joint venture, a corporation, a trust, an unincorporated  organization  or  a
Governmental Entity or any other legal entity.

      "PRINCIPAL" means the outstanding principal amount of this Note as of any
date of determination.

      "PUBLIC  DISCLOSURE"  or  "PUBLICLY  DISCLOSE" means the Company's public
dissemination  of  information  through  the filing  via  the  Electronic  Data
Gathering, Analysis, and Retrieval system  of  the  SEC of a Periodic Report or
Current Report disclosing such information pursuant to  the requirements of the
1934 Act.

      "REDEMPTION  PREMIUM"  means,  with  respect  to  any  Early   Redemption
Principal  and  Interest  Amount,  twenty  percent  (20%)  of  any  such  Early
Redemption Principal and Interest Amount.

      "SEC" means the U.S. Securities and Exchange Commission, or any successor
thereto.

      "U.S." means the United States of America.











                                 Appendix -