Exhibit
4.20


 


AMENDED AND RESTATED PLEDGE AGREEMENT


 


AMENDED AND RESTATED PLEDGE AGREEMENT, dated as of
October 31, 2007 (as amended, restated or otherwise modified from time to
time, this “Agreement”), made by
WENTWORTH ENERGY, INC., a company organized under the laws of the State of
Oklahoma (“Pledgor”), in favor of
CASTLERIGG MASTER INVESTMENTS LTD., a company organized under the laws of the
British Virgin Islands, in its capacity as collateral agent (in such capacity,
the “Collateral Agent”) for the benefit of
the Buyers (as defined below).


 


W  I
T  N  E  S  S  E  T  H:


 


A.            Pledgor and each party listed as a “Buyer” on the
Schedule of Buyers attached thereto (collectively, the “Buyers”)
are parties to that certain Securities Purchase Agreement, dated as of July 24,
2006 (as amended, restated or otherwise modified from time to time prior to the
date hereof, the “Existing  Securities Purchase Agreement”), pursuant
to which, among other things, the Buyers purchased from Pledgor an aggregate
original principal amount of $32,350,000 of senior secured convertible notes
(as amended, restated or otherwise modified from time to time prior to the date
hereof, the “Existing Notes”).


 


B.            Contemporaneously with the consummation of the
transactions contemplated by the Existing Securities Purchase Agreement, the
following transactions (among others) occurred: (i) Wentworth Oil & Gas,
Inc., a Nevada corporation and subsidiary of Pledgor (“WOG”),
entered into that certain Guaranty, dated as of July 25, 2006, in favor of the
Collateral Agent for the benefit of the Buyers (said guaranty, as amended,
restated or otherwise modified from time to time prior to the date hereof, the “Existing WOG Guaranty”);
(ii) Pledgor and WOG entered into that certain Security Agreement, dated as of
July 25, 2006, in favor of the Collateral Agent for the benefit of the Buyers,
as subsequently amended by that certain Joinder Agreement, dated as of August
8, 2006 (the “2006 Joinder Agreement”), in favor
of the Collateral Agent for the benefit of the Buyers, to join Barnico
Drilling, Inc., a Texas corporation (“Barnico”), as a
party thereto and collateral grantor thereunder (said security agreement, as
amended by the 2006 Joinder Agreement, and as otherwise amended, restated or
otherwise modified from time to time prior to the date hereof, the “Existing Security
Agreement”); and (iii) Pledgor and WOG entered into that certain
Pledge Agreement, dated as of July 25, 2006, in favor of Collateral Agent for
the benefit of the Buyers, as amended by that certain Pledge Amendment, dated
August 8, 2006 (the “2006 Pledge Amendment”),
to include as collateral thereunder the shares of Barnico capital stock
referenced in the 2006 Pledge Amendment (said pledge agreement, as amended by
the 2006 Pledge Amendment, and as otherwise amended, restated or otherwise
modified from time to time prior to the date hereof, the “Existing
Pledge Agreement”).


 


C.            As contemplated by the Existing Securities Purchase
Agreement, Pledgor entered into certain deeds of trust encumbering certain real
property and personal property of Pledgor (said deeds of trust, as amended,
restated or otherwise modified from time to time prior to the date hereof, the “Existing Deeds of Trust”), in favor of the trustee
referenced therein for the benefit of the Collateral Agent for the benefit of
the Buyers.


 

















 


D.            Barnico’s execution and delivery of the 2006 Joinder
Agreement was effected contemporanously with Pledgor’s purchase of all of the
outstanding stock of Barnico.  Also in
conjunction with that acquisition by Pledgor, Barnico entered into that certain
Guaranty, dated as of August 8, 2006 (said guaranty, as amended, restated or
otherwise modified from time to time prior to the date hereof, the “Existing Barnico Guaranty”), in favor of the Collateral
Agent for the benefit of the Buyers.


 


D.            Pledgor and the
Buyers, severally, are entering into those certain Amendment Agreements, each
dated as of the date hereof (the “Amendment Agreements”),
pursuant to which (among other things) Pledgor and the Buyers have agreed to
amend the Existing Securities Purchase Agreement (as so amended, and as
thereafter amended, restated or otherwise modified from time to time, the “Securities Purchase Agreement”) to provide for, among other
things, the following: (i) the amendment and restatement of the Existing
Barnico Guaranty by Barnico’s execution and delivery of that certain Amended
and Restated Barnico Guaranty, in the form attached as an exhibit to the
Amendment Agreements (said amended and restated guaranty, as thereafter
amended, restated or otherwise modified from time to time, the “Barnico Guaranty”); (ii) the amendment and restatement of
all of the Existing Notes by Pledgor’s issuance of amended and restated notes
therefor, in the form attached as an exhibit to the Amendment Agreements (said
amended and restated notes, as executed and delivered, and as thereafter,
amended, restated or otherwise modified from time to time, the “Amended and Restated Notes”); (iii) Pledgor’s issuance and
sale to one of the Buyers of a new senior secured convertible note in the form
attached as an exhibit to the Amendment Agreements (said new note, as executed
and delivered, and as thereafter amended, restated or otherwise modified from
time to time, the “New Note”;
collectively with the Amended and Restated Notes, the “Notes”);
(iv) the amendment and restatement of the Existing Pledge Agreement by the
execution and delivery of this Agreement; (v) the amendment and restatement of
the Existing Security Agreement, in the form attached as an exhibit to the
Amendment Agreements (said amended and restated security agreement, as executed
and delivered, and as thereafter amended, restated or otherwise modified from
time to time, the “Security Agreement”);
(vi) the amendment and restatement of the Existing Deeds of Trust heretofore
filed in Anderson, Freestone, Jones and Leon Counties, Texas, in the form
attached as an exhibit to the Amendment Agreements (said amended and restated
deeds of trust, as executed and delivered, and as thereafter amended, restated or
otherwise modified from time to time, the “Deeds of Trust”);
and (vii) to the extent not heretofore terminated, the termination of the
Existing Deeds of Trust filed in Archer, Pecos and Wichita Counties, Texas.


 


E.             WOG has been
dissolved and, prior hereto or contemporaneously herewith, WOG is being
released from all of its obligations under the Existing WOG Guaranty, the
Existing Pledge Agreement and the Existing Security Agreement.


 


F.             In order to induce
each of the Buyers to execute and deliver its respective Amendment Agreement
and perform its respective obligations under the Securities Purchase Agreement,
Pledgor has agreed to execute and deliver to the Collateral Agent, for the
benefit of the Buyers, this Agreement, which amends, restates and supersedes
the Existing Pledge Agreement.


 


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NOW, THEREFORE, in consideration of the premises and the agreements
herein, and in order to induce each of the Buyers to execute and deliver its
respective Amendment Agreement and to perform its respective obligations under
the Securities Purchase Agreement, Pledgor agrees with the Collateral Agent,
for the benefit of the Buyers, as follows:


 


SECTION 1.           Definitions
and Rules of Interpretation.


 


(a)           Definitions.  Reference is made to the Securities Purchase
Agreement and the Notes for a statement of the terms thereof.  All terms used in this Agreement which are
defined in the Securities Purchase Agreement or the Notes or in Article 8 or
Article 9 of the Uniform Commercial Code as in effect from time to time in the
State of New York (the “Code”),
and which are not otherwise defined herein, shall have the same meanings herein
as set forth therein; provided that terms used herein which are defined
in the Code as in effect in the State of New York on the date hereof shall
continue to have the same meaning notwithstanding any replacement or amendment
of such statute.


 


(b)           Rules of Interpretation.  Except as otherwise expressly provided in
this Agreement, the following rules of interpretation apply to this Agreement:
(i) the singular includes the plural and the plural includes the singular; (ii)
“or” and “any” are not exclusive and “include” and “including” are not
limiting; (iii) a reference to any agreement or other contract includes
permitted supplements and amendments; (iv) a reference to a law includes any
amendment or modification to such law and any rules or regulations issued
thereunder; (v) a reference to a person includes its permitted successors and
assigns; and (vi) a reference in this Agreement to an Article, Section, Annex,
Exhibit or Schedule is to the Article, Section, Annex, Exhibit or Schedule of
this Agreement.


 


SECTION 2.           Pledge
and Grant of Security Interest.


 


(a)           As
collateral security for all of the “Obligations” (as defined in Section 3
hereof), Pledgor hereby pledges and assigns and grants to the Collateral Agent
a continuing security interest in, and Lien on, all of Pledgor’s right, title
and interest in and to the following (collectively, the “Collateral”):


 


(i)            all
present, as set forth in Schedule I, and all future, issued and
outstanding shares of capital stock, or other equity or investment securities
of, or partnership, membership, or joint venture interests in, each Subsidiary
(as defined in the Securities Purchase Agreement) and Redrock Energy (as
defined below), whether now owned or hereafter acquired by Pledgor and whether
or not evidenced or represented by any stock certificate, certificated security
or other instrument, together with the certificates representing such equity
interests, all options and other rights, contractual or otherwise, in respect
thereof and all dividends, distributions, cash, instruments, investment
property and any other property (including, but not limited to, any stock dividend
and any distribution in connection with a stock split) from time to time
received, receivable or otherwise distributed in respect of or in exchange for
any or all of the foregoing and all cash and noncash proceeds thereof (other
than the Excluded Shares and the Excluded Shares Rights (each as defined
below)) (subject to the foregoing exclusions, collectively the “Pledged Shares”);


 


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(ii)           all
present and future increases, profits, combinations, reclassifications, and
substitutes and replacements for all or part of the foregoing Collateral
heretofore described;


 


(iii)          all
investment property, financial assets, securities, capital stock, other equity
interests, stock options and commodity contracts of Pledgor (other than the
Excluded Shares and the Excluded Shares Rights), all notes, debentures, bonds,
promissory notes or other evidences of indebtedness payable or owing to
Pledgor, and all other assets now or hereafter received or receivable with
respect to the foregoing;


 


(iv)          all
security entitlements of Pledgor in any and all of the foregoing; and


 


(v)           all
proceeds (including proceeds of proceeds) of any and all of the foregoing;


 


in
each case, whether now owned or hereafter acquired by Pledgor and howsoever its
interest therein may arise or appear (whether by ownership, security interest,
Lien, claim or otherwise).


 


(b)           Collateral Agent acknowledges and
agrees individually and as collateral agent for the Buyers that: (i) Pledgor is
not pledging, assigning, or granting to Collateral Agent or the Buyers pursuant
hereto or pursuant to the Security Agreement or any other Security Document the
capital stock of Redrock Energy, Inc. (f.k.a. Redrock Oil Sands, Inc.), a
Nevada corporation (the “Redrock Energy”),
described on Schedule II (the “Excluded Shares”),
or any other shares, rights, or dividends or other proceeds paid or payable to
the holder or holders of the Excluded Shares (collectively, the “Excluded Shares Rights”); and (ii) Pledgor shall hold the
Excluded Shares and Excluded Share Rights free and clear of any security
interest, pledge or other Lien of Collateral Agent or Buyers under this
Agreement, the Security Agreement, or any other Security Document, or
otherwise.  Collateral Agent further
agrees individually and as collateral agent for the Buyers that notwithstanding
any provision to the contrary contained herein, or in the Security Agreement or
any other Security Document or Transaction Document, Pledgor may distribute the
Excluded Shares and Excluded Share Rights to the shareholders of Pledgor in
accordance with Section 14(e) of the Notes.


 


SECTION
3.           Security for Obligations.  The security interest created hereby in the
Collateral constitutes continuing collateral security for all of the following
obligations, whether now existing or hereafter incurred (collectively, the “Obligations”):


 


(a)           for so long as the Notes are
outstanding, the payment by Pledgor, as and when due and payable (by scheduled
maturity, required prepayment, acceleration, demand or otherwise), of all
amounts from time to time owing by it in respect of the Securities Purchase
Agreement, the Notes and the other Transaction
Documents, and (ii) the payment by Barnico, as and when due and payable,
of all “Guaranteed Obligations”
under (as defined in) the Barnico Guaranty, including, without limitation, (A)
all principal of and interest on the Notes (including, without limitation, all
interest that accrues after the commencement of any bankruptcy proceeding of
Pledgor, whether or not the payment of such interest is unenforceable or is not
allowable due to the existence of such bankruptcy proceeding), and (B) all
fees, commissions, 


 


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expense reimbursements, indemnifications and
all other amounts due or to become due under any of the Transaction Documents;
and


 


(b)           for so long as the Notes are
outstanding, the due performance and observance by Pledgor of all of its other
obligations from time to time existing in respect of any of the Transaction
Documents.


 


SECTION 4.           Delivery
of the Collateral.


 


(a)           All certificates currently
representing the Pledged Shares shall be delivered to the Collateral Agent on
or prior to the execution and delivery of this Agreement, and in all cases
shall be deemed to be held pursuant to this Agreement.  All other promissory notes, certificates and
instruments constituting Collateral from time to time or required to be pledged
to the Collateral Agent pursuant to the terms of this Agreement (the “Additional Collateral”) shall be delivered
to the Collateral Agent promptly upon receipt thereof by or on behalf of
Pledgor.  All such promissory notes,
certificates and instruments shall be held by the Collateral Agent pursuant
hereto and shall be delivered in suitable form for transfer by delivery or
shall be accompanied by duly executed instruments of transfer or assignment or
undated stock powers executed in blank, all in form and substance reasonably
satisfactory to the Collateral Agent.  If
any Collateral consists of uncertificated securities, unless the immediately
following sentence is applicable thereto, Pledgor shall cause the Collateral
Agent (or its designated custodian, nominee or other designee) to become the
registered holder thereof, or cause each issuer of such securities to agree
that it will comply with instructions originated by the Collateral Agent (or
its designated custodian, nominee or other designee) with respect to such
securities without further consent by Pledgor. 
If any Collateral consists of security entitlements, Pledgor shall
transfer such security entitlements to the Collateral Agent (or its designated
custodian, nominee or other designee) or cause the applicable securities
intermediary to agree that it will comply with entitlement orders originated by
the Collateral Agent (or its designated custodian, nominee or other designee)
without further consent by Pledgor.


 


(b)           Promptly upon the receipt by Pledgor
of any Additional Collateral, a Pledge Amendment, duly executed by Pledgor, in
substantially the form of Annex I hereto (a “Pledge Amendment”), shall be delivered to the Collateral
Agent, in respect of the Additional Collateral which is or are to be pledged
pursuant to this Agreement, which Pledge Amendment shall from and after
delivery thereof constitute part of Schedule I hereto.  Pledgor hereby authorizes the Collateral
Agent to attach each Pledge Amendment to this Agreement and agrees that all
promissory notes, certificates or instruments listed on any Pledge Amendment
shall for all purposes hereunder constitute Collateral and Pledgor shall be
deemed upon delivery thereof to have made the representations and warranties
set forth in Section 5 hereof with respect to such Additional Collateral
as of the date of the Pledge Amendment.


 


(c)           If Pledgor shall receive, by virtue
of such Pledgor’s being or having been an owner of any Collateral, any (i)
stock certificate (including, without limitation, any certificate representing
a stock dividend or distribution in connection with any increase or reduction of
capital, reclassification, merger, consolidation, sale of assets, combination
of shares, stock split, spin-off or split-off), promissory note or other
instrument, (ii) option or right, whether as an addition to, substitution for,
or in exchange for, any Collateral, or otherwise, (iii) dividends 


 


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payable in cash (except such dividends
permitted to be retained by Pledgor pursuant to Section 7 hereof) or in
securities or other property or (iv) dividends, distributions, cash,
instruments, investment property and other property in connection with a
partial or total liquidation or dissolution or in connection with a reduction
of capital, capital surplus or paid-in surplus, Pledgor shall receive such
stock certificate, promissory note, instrument, option, right, payment or
distribution in trust for the benefit of the Collateral Agent, shall segregate
it from Pledgor’s other property and shall deliver it forthwith to the
Collateral Agent in the exact form received, with any necessary endorsement
and/or appropriate stock powers duly executed in blank, to be held by the
Collateral Agent as Collateral and as further collateral security for the
Obligations.


 


SECTION 5.           Representations
and Warranties.  Pledgor represents
and warrants as of the date of this Agreement as follows:


 


(a)           Pledgor (i) is a corporation duly
organized, validly existing and in good standing under the laws of the state of
its organization, and (ii) has all corporate power and authority to execute,
deliver and perform this Agreement.


 


(b)           The execution, delivery and
performance by Pledgor of this Agreement (i) have been duly authorized by all
necessary corporate action, (ii) do not and will not contravene its charter or
bylaws, or any applicable law or any contractual restriction binding on or
affecting it or any of its properties, and (iii) do not and will not result in
or require the creation of any Lien upon or with respect to any of its
properties other than pursuant to this Agreement.


 


(c)           The issuers of the Pledged Shares set
forth in Schedule I hereto are Pledgor’s only Subsidiaries existing on
the date hereof, provided that Redrock Energy is not a Subsidiary.  The Pledged Shares have been duly authorized
and validly issued, are fully paid and nonassessable and the holders thereof
are not entitled to any preemptive first refusal or other similar rights.  Except as noted in Schedule I hereto,
the Pledged Shares constitute 100% of the issued shares of capital stock,
partnership interests or membership or other equity interests, as applicable,
of the Subsidiaries.  All other shares of
stock constituting Collateral will be, when issued, duly authorized and validly
issued, fully paid and nonassessable.


 


(d)           Pledgor is and will be at all times
the legal and beneficial owners of the Collateral free and clear of any Lien,
other than Permitted Liens.


 


(e)           The exercise by the Collateral Agent
of any of its rights and remedies hereunder will not contravene any law or any
contractual restriction binding on or affecting Pledgor or any of the
properties of Pledgor and will not result in or require the creation of any
Lien upon or with respect to any of the properties of Pledgor other than
pursuant to this Agreement and the other Transaction Documents.


 


(f)            No authorization or approval or
other action by, and no notice to or filing with, any governmental authority is
required to be obtained by Pledgor for (i) the due execution, delivery and
performance by Pledgor of this Agreement, (ii) the grant by Pledgor, or subject
to the Collateral Agent’s having possession of certificates, instruments,
securities entitlements and cash constituting Collateral, the perfection of the
security interest and Lien 


 


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purported to be created hereby in the
Collateral or (iii) the exercise by the Collateral Agent of any of its rights
and remedies hereunder, except as may be required in connection with any sale
of any Collateral by laws affecting the offering and sale of securities generally.


 


(g)           This Agreement creates a valid
security interest and Lien in favor of the Collateral Agent in the Collateral,
as security for the Obligations.  The
Collateral Agent’s having possession of the promissory notes included in the
Collateral, the certificates representing the Pledged Shares and all other
certificates, instruments and cash constituting Collateral from time to time
results in the perfection of the security interest in such Collateral.  Such security interest and Lien is, or in the
case of Collateral in which Pledgor obtains rights after the date hereof, will
be, a perfected Lien in such Collateral if the Collateral Agent has possession
of such Collateral.  All action necessary
to perfect and protect such security interest and Lien has been duly taken,
except for the Collateral Agent’s having possession of certificates,
instruments, securities entitlements and cash constituting Collateral after the
date hereof.


 


SECTION 6.           Covenants as to the Collateral.  So long as any Obligations (other than
inchoate indemnity obligations) shall remain outstanding, Pledgor will, unless
the Collateral Agent shall otherwise consent in writing:


 


(a)           keep adequate records concerning the
Collateral owned or purported to be owned by it, and permit the Collateral Agent,
or any designees or representatives thereof at any time or from time to time to
examine and make copies of and abstracts from such records;


 


(b)           at the Pledgor’s expense, promptly
deliver to the Collateral Agent a copy of each material notice or other
material communication received by Pledgor in respect of the Collateral;


 


(c)           at Pledgor’s expense, defend the
Collateral Agent’s right, title and security interest in and to the Collateral
against the claims of any Person (other than the holders of Permitted Liens);


 


(d)           at Pledgor’s expense, at any time and
from time to time, promptly execute and deliver all further instruments and
documents and take all further action that may be necessary or that the
Collateral Agent may reasonably request in order to (i) perfect and
protect, or maintain the perfection of, the security interest and Lien
purported to be created hereby, (ii) enable the Collateral Agent to exercise
and enforce its rights and remedies hereunder in respect of the Collateral or
(iii) otherwise effect the purposes of this Agreement, including, without
limitation, delivering to the Collateral Agent irrevocable proxies in respect
of the Collateral registered in the name of Pledgor, except for Collateral
which Pledgor is entitled to vote under the terms of Section 7 hereof;


 


(e)           not sell, assign (by operation of law
or otherwise), exchange or otherwise dispose of any Collateral or any interest
therein except in the ordinary course of business or as expressly permitted by
the Securities Purchase Agreement or the Notes;


 


(f)            not create or suffer to exist any
Lien, upon or with respect to any Collateral except for Permitted Liens;


 


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(g)           not make or consent to any amendment
or other modification or waiver with respect to any Collateral or enter into
any agreement or permit to exist any restriction with respect to any Collateral
other than pursuant to the Transaction Documents;


 


(h)           except as expressly permitted by the
Securities Purchase Agreement, not permit the issuance of (i) any additional
shares of any class of capital stock, partnership interests, member interests
or other equity of any Subsidiary, (ii) any securities convertible voluntarily
by the holder thereof or automatically upon the occurrence or non-occurrence of
any event or condition into, or exchangeable for, any such shares of capital
stock or (iii) any warrants, options, contracts or other commitments entitling
any Person to purchase or otherwise acquire any such shares of capital stock;


 


(i)            not issue any stock certificate,
certificated security or other instrument to evidence or represent any shares
of capital stock, any partnership interest or membership interest described in Schedule
I hereto, unless such stock certificate, certificated security or other
instrument is delivered to the Collateral Agent to be held as Collateral
pursuant hereto; and


 


(j)            not take or fail to take any action
which would in any manner impair the validity or enforceability of the
Collateral Agent’s security interest in and Lien on any Collateral.


 


SECTION 7.           Voting Rights, Dividends, Etc. in
Respect of the Collateral.


 


(a)           So long as no Event of Default (as
defined in the Notes) (an “Event of Default”)  shall have occurred and be continuing:


 


(i)            Pledgor may exercise any and all voting and other
consensual rights pertaining to any Collateral for any purpose not inconsistent
with the terms of this Agreement, the Securities Purchase Agreement or the
other Transaction Documents; provided, however, that
(A) Pledgor will not exercise or refrain from exercising any such right,
as the case may be, if the Collateral Agent gives it notice that, in the
Collateral Agent’s judgment, such action (or inaction) is reasonably likely to
have a Material Adverse Effect and (B) Pledgor will give the Collateral
Agent at least five (5) Business Days’ notice of the manner in which it intends
to exercise, or the reasons for refraining from exercising, any such right
which is reasonably likely to have a Material Adverse Effect;


 


(ii)           Pledgor may receive and retain any and all dividends,
interest or other distributions paid in respect of the Collateral to the extent
permitted by the Securities Purchase Agreement; provided, however,
that any and all (A) dividends and interest paid or payable other than in cash
in respect of, and instruments (other than checks) and other property received,
receivable or otherwise distributed in respect of or in exchange for, any
Collateral, (B) dividends and other distributions paid or payable in cash in
respect of any Collateral in connection with a partial or total liquidation or
dissolution or in connection with a reduction of capital, capital surplus or
paid-in surplus, and (C) cash paid, payable or otherwise distributed in
redemption of, or in exchange for, any Collateral, together with any dividend,
distribution, interest or 


 


8

















 


other payment which at the time of such dividend,
distribution, interest or other payment was not permitted by the Securities
Purchase Agreement, shall be, and shall forthwith be delivered to the
Collateral Agent to hold as, Collateral and shall, if received by Pledgor, be
received in trust for the benefit of the Collateral Agent, shall be segregated
from the other property or funds of Pledgor, and shall be forthwith delivered
to the Collateral Agent in the exact form received with any necessary
indorsement and/or appropriate stock powers duly executed in blank, to be held
by the Collateral Agent as Collateral and as further collateral security for
the Obligations; and


 


(iii)          the Collateral Agent will execute and deliver (or cause to
be executed and delivered) to Pledgor all such proxies and other instruments as
Pledgor may reasonably request for the purpose of enabling Pledgor to exercise
the voting and other rights which it is entitled to exercise pursuant to
paragraph (i) of this Section 7(a) and to receive the dividends,
distributions, interest and other payments which it is authorized to receive
and retain pursuant to paragraph (ii) of this Section 7(a), in each
case, to the extent that the Collateral Agent has possession of such
Collateral.


 


(b)           Upon the occurrence and during the
continuance of an Event of Default:


 


(i)            all rights of Pledgor to exercise the voting and other
consensual rights which it would otherwise be entitled to exercise pursuant to
paragraph (i) of subsection (a) of this Section 7, and to receive
the dividends, distributions, interest and other payments which it would
otherwise be authorized to receive and retain pursuant to paragraph
(ii) of subsection (a) of this Section 7, shall cease, and all
such rights shall thereupon become vested in the Collateral Agent which shall
thereupon have the sole right to exercise such voting and other consensual
rights and to receive and hold as Collateral such dividends, distributions,
interest and other payments;


 


(ii)           without limiting the generality of the foregoing, the
Collateral Agent may at its option exercise any and all rights of conversion,
exchange, subscription or any other rights, privileges or options pertaining to
any of the Collateral as if it were the absolute owner thereof, including,
without limitation, the right to exchange, in its discretion, any and all of
the Collateral upon the merger, consolidation, reorganization, recapitalization
or other adjustment of any issuer of the Collateral or upon the exercise by any
issuer of the Collateral of any right, privilege or option pertaining to any
Collateral, and, in connection therewith, to deposit and deliver any and all of
the Collateral with any committee, depository, transfer collateral agent,
registrar or other designated collateral agent upon such terms and conditions
as it may determine; and


 


(iii)          all dividends, distributions, interest and other payments
which are received by Pledgor contrary to the provisions of paragraph (i) of
this Section 7(b) shall be received in trust for the benefit of the
Collateral Agent, shall be segregated from other funds of Pledgor, and shall be
forthwith paid over to the Collateral Agent as Collateral in the exact form
received with any necessary indorsement and/or appropriate stock powers duly
executed in blank, to be held by the Collateral Agent as Collateral and as
further collateral security for the Obligations.


 


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SECTION 8.           Additional
Provisions Concerning the Collateral.


 


(a)           Pledgor hereby (i) authorizes the Collateral Agent to file
one or more financing or continuation statements, and amendments thereto,
relating to the Collateral, without the signature of Pledgor where permitted by
law, (ii) ratifies such authorization to the extent that the Collateral Agent
has filed any such financing or continuation statements, or amendments thereto,
without the signature of Pledgor prior to the date hereof and (iii) authorizes
the Collateral Agent to execute any agreements, instruments or other documents
in Pledgor’s name and to file such agreements, instruments or other documents
that perfect, protect or enforce the security interest and Lien of the
Collateral Agent in the Collateral or as provided under Article 8 or Article 9
of the UCC in any appropriate filing office. 
Without limiting the generality of the foregoing, Pledgor hereby
ratifies and confirms the filing of any and all financing statements filed by
the Collateral Agent as secured party in connection with the transactions
contemplated by the Existing Pledge Agreement, and Pledgor agrees that any and
all such financing statements also shall apply to perfect the security interest
in the Collateral granted under this Agreement.


 


(b)           Pledgor hereby irrevocably appoints the Collateral Agent
as its attorney-in-fact and proxy, with full authority in the place and stead
and in its name or otherwise, from time to time in the Collateral Agent’s
discretion to take any action and to execute any instrument which the
Collateral Agent may deem necessary or advisable to accomplish the purposes of
this Agreement (subject to the rights of Pledgor under Section 7(a)
hereof), including, without limitation, to receive, indorse and collect all
instruments made payable to Pledgor representing any dividend, interest payment
or other distribution in respect of any Collateral and to give full discharge
for the same.  This power is coupled with
an interest and is irrevocable until the termination of this Agreement in
accordance with Section 13(e) hereof.


 


(c)           If Pledgor fails to perform any agreement or obligation
contained herein, the Collateral Agent itself may perform, or cause performance
of, such agreement or obligation, and the expenses of the Collateral Agent
incurred in connection therewith shall be payable by Pledgor pursuant to Section
10 hereof and shall be secured by the Collateral.


 


(d)           Other than the exercise of reasonable care to assure the
safe custody of the Collateral while held hereunder, the Collateral Agent shall
have no duty or liability to preserve rights pertaining thereto and shall be
relieved of all responsibility for the Collateral upon surrendering it or
tendering surrender of it to Pledgor. 
The Collateral Agent shall be deemed to have exercised reasonable care
in the custody and preservation of the Collateral in its possession if the
Collateral is accorded treatment substantially equal to that which the
Collateral Agent accords its own property, it being understood that the
Collateral Agent shall not have responsibility for (i) ascertaining or taking
action with respect to calls, conversions, exchanges, maturities, tenders or
other matters relating to any Collateral, whether or not the Collateral Agent
has or is deemed to have knowledge of such matters, or (ii) taking any
necessary steps to preserve rights against any parties with respect to any
Collateral.


 


(e)           The powers conferred on the Collateral Agent hereunder are
solely to protect its interest in the Collateral and shall not impose any duty
upon it to exercise any such powers. 
Except for the safe custody of any Collateral in its possession and the
accounting for 


 


10

















 


monies actually received by it hereunder, the
Collateral Agent shall have no duty as to any Collateral or as to the taking of
any necessary steps to preserve rights against prior parties or any other
rights pertaining to any Collateral.


 


(f)            Upon the occurrence and during the continuation of any
Event of Default, the Collateral Agent may at any time in its discretion (i)
without notice to Pledgor, transfer or register in the name of the Collateral
Agent or any of its nominees any or all of the Collateral, subject only to the
revocable rights of Pledgor under Section 7(a) hereof, and (ii) exchange
certificates or instruments constituting Collateral for certificates or
instruments of smaller or larger denominations.


 


SECTION 9.           Remedies Upon Default.  If any Event of Default shall have occurred
and be continuing:


 


(a)           The Collateral Agent may exercise in respect of the
Collateral, in addition to other rights and remedies provided for herein or
otherwise available to it, all of the rights and remedies of a secured party on
default under the Code then in effect in the State of New York; and, without
limiting the generality of the foregoing and without notice except as specified
below, sell the Collateral or any part thereof in one or more parcels at public
or private sale, at any exchange or broker’s board or elsewhere, at such price
or prices and on such other terms as the Collateral Agent may deem commercially
reasonable.  Pledgor agrees that, to the
extent notice of sale shall be required by law, at least ten (10) days’ notice
to Pledgor of the time and place of any public sale or the time after which any
private sale is to be made shall constitute reasonable notification.  The Collateral Agent shall not be obligated
to make any sale of Collateral regardless of notice of sale having been
given.  The Collateral Agent may adjourn
any public or private sale from time to time by announcement at the time and
place fixed therefor, and such sale may, without further notice, be made at the
time and place to which it was so adjourned.


 


(b)           Pledgor recognizes that it may be impracticable to effect
a public sale of all or any part of the Pledged Shares or any other securities
constituting Collateral and that the Collateral Agent may, therefore, determine
to make one or more private sales of any such securities to a restricted group
of purchasers who will be obligated to agree, among other things, to acquire
such securities for its own account, for investment and not with a view to the
distribution or resale thereof.  Pledgor
acknowledges that any such private sale may be at prices and on terms less
favorable to the seller than the prices and other terms which might have been
obtained at a public sale and, notwithstanding the foregoing, agrees that such
private sales shall be deemed to have been made in a commercially reasonable
manner and that the Collateral Agent shall have no obligation to delay sale of
any such securities for the period of time necessary to permit the issuer of
such securities to register such securities for public sale under the
Securities Act of 1933, as amended (the “Securities
Act”).  Pledgor further
acknowledges and agrees that any offer to sell such securities which has been
(i) publicly advertised on a bona fide basis in a newspaper or other
publication of general circulation in the financial community of New York, New
York (to the extent that such an offer may be so advertised without prior
registration under the Securities Act) or (ii) made privately in the manner
described above to not less than fifteen (15) bona  fide offerees
shall be deemed to involve a “public disposition” for the purposes of Section
9-610 of the Code (or any successor or similar, applicable statutory 


 


11

















 


provision) as then in effect in the State of New
York, notwithstanding that such sale may not constitute a “public offering”
under the Securities Act, and that the Collateral Agent may, in such event, bid
for the purchase of such securities.


 


(c)           Any cash held by the Collateral Agent as Collateral and
all cash proceeds received by the Collateral Agent in respect of any sale of,
collection from, or other realization upon, all or any part of the Collateral
shall be applied (after payment of any amounts payable to the Collateral Agent
pursuant to Section 10 hereof) by the Collateral Agent against all or
any part of the Obligations in such order as the Collateral Agent shall elect
consistent with the provisions of the Securities Purchase Agreement.


 


(d)           In the event that the proceeds of any such sale,
collection or realization are insufficient to pay all amounts to which the
Collateral Agent is legally entitled, Pledgor shall be liable for the
deficiency, together with interest thereon at the highest rate specified in the
Notes for interest on overdue principal thereof or such other rate as shall be
fixed by applicable law, together with the costs of collection and the
reasonable fees, costs and expenses of any attorneys employed by the Collateral
Agent to collect such deficiency.


 


SECTION 10.         Indemnity and Expenses.


 


(a)           Pledgor hereby agrees to indemnify and hold the Collateral
Agent (and all of its officers, directors, employees, attorneys, and
consultants) harmless from and against any and all claims, damages, losses,
liabilities, obligations, penalties, fees, costs and expenses (including,
without limitation, reasonable legal fees and disbursements of counsel) to the
extent that they arise out of or otherwise result from this Agreement
(including, without limitation, enforcement of this Agreement), except such
claims, damages, losses, liabilities, obligations, penalties, fees, costs and
expenses resulting from such Person’s gross negligence or willful misconduct as
determined by a court of competent jurisdiction.


 


(b)           Pledgor shall be obligated for, and will upon demand pay
to the Collateral Agent the reasonable amount of any and all out-of-pocket
costs and expenses, including the reasonable fees and disbursements of the
Collateral Agent’s counsel and of any experts which the Collateral Agent may
incur in connection with (i) the preparation, negotiation, execution, delivery,
recordation, administration, amendment, waiver or other modification or
termination of this Agreement, (ii) the custody, preservation, use or operation
of, or the sale of, collection from, or other realization upon, any Collateral,
(iii) the exercise or enforcement of any of the rights of the Collateral Agent
hereunder, or (iv) the failure by Pledgor to perform or observe any of the
provisions hereof.


 


SECTION 11.         Notices,
Etc.  All notices and other
communications provided for hereunder shall be in writing and shall be mailed
(by certified mail, postage prepaid and return receipt requested), sent by
Federal Express or other recognized courier service (return receipt requested),
telecopied or delivered by hand, if to Pledgor, to it at the address specified
for Pledgor in the Securities Purchase Agreement or if to the Collateral Agent,
to it at the address specified in the Securities Purchase Agreement; or as to
either such Person at such other address as shall be designated by such Person
in a written notice to such other Person complying as to delivery with the
terms of this Section 11.  All
such notices and other communications shall be 


 


 


12

















 


effective (i) if sent by certified mail,
postage prepaid, return receipt requested, when received or three (3) Business
Days after mailing, whichever first occurs, (ii) if telecopied, when
transmitted and confirmation is received, provided same is on a Business Day
and, if not, on the next Business Day or (iii) if delivered by hand or sent by
Federal Express or other recognized courier service (return receipt requested),
upon delivery, provided same is on a Business Day and, if not, on the next
Business Day.  


 


SECTION 12.         Security Interest Absolute.  All rights of the Collateral Agent, all Liens
and all obligations of Pledgor hereunder shall be absolute and unconditional
irrespective of:  (i) any lack of
validity or enforceability of the Securities Purchase Agreement or any other Transaction
Document, (ii) any change in the time, manner or place of payment of, or in any
other term in respect of, all or any of the Obligations, or any other amendment
or waiver of or consent to any departure from the Securities Purchase Agreement
or any other Transaction Document, (iii) any exchange or release of, or
non-perfection of any Lien on any Collateral, or any release or amendment or
waiver of or consent to departure from any guaranty, for all or any of the
Obligations, or (iv) any other circumstance which might otherwise constitute a
defense available to, or a discharge of, Pledgor in respect of the Obligations
(other than the payment in full of the Obligations).  All authorizations and agencies contained
herein with respect to any of the Collateral are irrevocable and powers coupled
with an interest.


 


SECTION 13.         Miscellaneous.


 


(a)           No amendment of any provision of this Agreement shall be
effective unless it is in writing and signed by Pledgor and the Collateral
Agent.  No waiver of any provision of
this Agreement, and no consent to any departure therefrom by Pledgor or the
Collateral Agent, shall be effective unless it is in writing and signed by
Pledgor and the Collateral Agent, and then such waiver or consent shall be
effective only in the specific instance and for the specific purpose for which
given.


 


(b)           No failure on the part of the Collateral Agent to
exercise, and no delay in exercising, any right hereunder or under any other
Transaction Document shall operate as a waiver hereof or thereof; nor shall any
single or partial exercise of any such right preclude any other or further
exercise hereof or thereof or the exercise of any other right.  The rights and remedies of the Collateral
Agent provided herein and in the other Transaction Documents are cumulative and
are in addition to, and not exclusive of, any rights or remedies provided by
law.  The rights of the Collateral Agent
under any Transaction Document against any party thereto are not conditional or
contingent on any attempt by the Collateral Agent to exercise any of its rights
under any other Transaction Document against such party or against any other
Person.


 


(c)           Any provision of this Agreement which is prohibited or
unenforceable in any jurisdiction shall, as to such jurisdiction, be
ineffective to the extent of such prohibition or unenforceability without
invalidating the remaining portions hereof in such jurisdiction or the validity
or enforceability of any provision of this Agreement in any other jurisdiction.


 


(d)           This Agreement shall create a continuing security interest
in and Lien on the Collateral and shall (i) remain in full force and effect
until the termination of this 


 


13

















 


Agreement in accordance with Section 13(e)
hereof and (ii) be binding on Pledgor and its successors and assigns and shall
inure, together with all rights and remedies of the Collateral Agent, to the
benefit of the Collateral Agent and its successors, transferees and assigns.  Without limiting the generality of clause
(ii) of the immediately preceding sentence, the Collateral Agent may assign or
otherwise transfer its rights and obligations under this Agreement and any
other Transaction Document to any other Person pursuant to the terms of the
Securities Purchase Agreement, and such other Person shall thereupon become
vested with all of the benefits in respect thereof granted to the Collateral
Agent herein or otherwise.  Upon any such
assignment or transfer, all references in this Agreement to the Collateral Agent
shall mean the assignee of the Collateral Agent.  None of the rights or obligations of Pledgor
hereunder may be assigned or otherwise transferred without the prior written
consent of the Collateral Agent, and any such assignment or transfer without the
consent of the Collateral Agent shall be null and void.


 


(e)           Notwithstanding anything to the contrary in this
Agreement, (i) this Agreement (along with all powers of attorney granted
hereunder) and the security interests and Lien created hereby shall terminate
and all rights to the Collateral shall revert to Pledgor upon the repayment in
full and /or complete conversion to equity securities of Pledgor of all
indebtedness obligations owed by Pledgor to the Buyers under the Notes
(including, without limitation, all principal, interest and fees related to the
Notes), and (ii) the Collateral Agent will, upon Pledgor’s request and at
Pledgor’s expense, (A) return to Pledgor such of the Collateral (to the extent
delivered to the Collateral Agent) as shall not have been sold or otherwise
disposed of or applied pursuant to the terms hereof, and (B) execute and
deliver to Pledgor, without recourse, representation or warranty, such
documents as Pledgor shall reasonably request to evidence such termination.


 


(f)            The internal laws, and not the laws of conflicts (to the
extent the application thereof would defer to the substantive laws of another
jurisdiction), of the State of New York shall govern the enforceability and
validity of this Agreement, the construction of its terms and the
interpretation of the rights and duties of the parties, except as required by
mandatory provisions of law and except to the extent that the perfection and
the effect of perfection or non-perfection of the security interest and Lien
created hereby, or remedies hereunder, in respect of any particular Collateral
are governed by the law of a jurisdiction other than the State of New York.


 


(g)           Each party to this Agreement hereby irrevocably and
unconditionally submits, for itself and its property, to the jurisdiction of
the United States District Court for the Southern District of New York sitting
in Manhattan or the Commercial Division, Civil Branch of the Supreme Court of
the State of New York sitting in New York County in connection with any suit,
action or proceeding directly or indirectly arising out of, under or in
connection with this Agreement or the other Transaction Documents or the
transactions contemplated hereby or thereby. 
No party to this Agreement may move to (i) transfer any such suit,
action or proceeding brought in such New York court or federal court to another
jurisdiction, (ii) consolidate any such suit, action or proceeding brought in
such New York court or federal court with a suit, action or proceeding in
another jurisdiction or (iii) dismiss any such suit, action or proceeding
brought in such New York court or federal court for the purpose of bringing the
same in another jurisdiction.  Each party
to this Agreement agrees that a final judgment in any such suit, action or proceeding
shall be conclusive and may be 


 


14

















 


enforced in any other jurisdiction by suit on the
judgment or in any other manner provided by law.  Each party to this Agreement hereby
irrevocably and unconditionally waives, to the fullest extent it may legally
and effectively do so, any objection which it may now or hereafter have to the
laying of venue of any suit, action or proceeding arising out of or relating to
this Agreement or the other Transaction Documents, in any New York court
sitting in the County of New York or any federal court sitting in the Southern
District of New York.


 


(h)           Pledgor irrevocably consents to the service of process of
any of the aforesaid courts in any such action, suit or proceeding by the
mailing of copies thereof by registered or certified mail (or any substantially
similar form of mail), postage prepaid, to Pledgor at its address determined in
accordance with Section 11 hereof, such service to become effective when
received or 10 days after such mailing, whichever first occurs.


 


(i)            Nothing contained herein shall affect the right of the
Collateral Agent to serve process in any other manner permitted by law or
commence legal proceedings or otherwise proceed against Pledgor or any property
of Pledgor in any other jurisdiction.


 


(j)            Pledgor irrevocably and unconditionally waives any right
it may have to claim or recover in any legal action, suit or proceeding
referred to in this Section any special, exemplary, punitive or consequential
damages.


 


(k)           EACH PARTY HERETO HEREBY WAIVES, TO THE FULLEST EXTENT
PERMITTED BY APPLICABLE LAW, ANY RIGHT IT MAY HAVE TO A TRIAL BY JURY IN
RESPECT OF ANY SUIT, ACTION OR PROCEEDING DIRECTLY OR INDIRECTLY ARISING OUT
OF, UNDER OR IN CONNECTION WITH THIS AGREEMENT OR OTHER TRANSACTION DOCUMENTS.


 


(l)            The headings herein are for convenience only, do not
constitute a part of this Agreement and shall not be deemed to limit or affect
any of the provisions hereof.  The
language used in this Agreement will be deemed to be the language chosen by the
parties to express their mutual intent, and no rules of strict construction
will be applied against any party.


 


(m)          This Agreement may be executed in any number of
counterparts and by different parties hereto in separate counterparts, each of
which shall be deemed to be an original, but all of which taken together shall
constitute one and the same agreement.


 


(n)           This Agreement reflects
the entire understanding of Pledgor and the Collateral Agent with respect to
the transactions contemplated hereby and shall not be contradicted or qualified
by any other agreement, oral or written, entered into before the date
hereof.  Without limiting the generality
of the foregoing, Pledgor and the Collateral Agent hereby agree that this
Agreement does hereby amend and restate, and completely replace, the Existing
Pledge Agreement, which shall have no further force or effect; and that WOG is
hereby released as a party under the Existing Pledge Agreement as amended and
restated hereby and discharged from any and all obligations and liabilities
thereunder.


 


[Signature Page Follows]


 


15

















 


IN WITNESS WHEREOF, Pledgor has caused this Agreement to be executed
and delivered by its officer thereunto duly authorized, as of the date first
above written.


 


	
   

  	
  WENTWORTH
  ENERGY, INC

  
	
   

  	
   

  
	
   

  	
  By:
  

  	
  /s/
  John Punzo

  	
   

  
	
   

  	
  Name:
  John Punzo

  
	
   

  	
  Title:
  Chief Executive Officer

  
	
   

  	
  Address:
  112 E. Oak Street, Suite 200

  
	
   

  	
  Palestine, Texas 75801

  
	
   

  	
   

  
	
   

  	
  Facsimile:
  817.288.0903

  



 


 

















 


ACCEPTED
AND AGREED:


 


CASTLERIGG MASTER INVESTMENTS LTD.,


as Collateral Agent


By: SANDELL ASSET MANAGEMENT CORP.


 


 


	
  By:
  

  	
  /s/
  Patrick T. Burke

  	
   

  	
   

  
	
  Name:
  Patrick T. Burke

  
	
  Title:
  Senior Managing Director

  



 

















 


SCHEDULE I
TO PLEDGE AGREEMENT


 


Pledged Shares


 


	
  Pledgor

  	
   

  	
  Name of
  Issuer

  	
   

  	
  Number
  of Shares

  	
   

  	
  % of
  Issuer’s Issued Shares

  	
   

  	
  Class

  	
   

  	
  Certificate

  No.(s)

  
	
  Wentworth Energy, Inc.

  	
   

  	
  Barnico Drilling, Inc.

  	
   

  	
  5,000

  	
   

  	
  100%

  	
   

  	
  Class A Voting

  	
   

  	
  A3

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
   

  	
   

  	
   

  	
   

  	
  15,000

  	
   

  	
  100%

  	
   

  	
  Class B Non-Voting

  	
   

  	
  B7

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  
	
  Wentworth Energy, Inc.

  	
   

  	
  Redrock Energy, Inc. (f./k./a.
  Redrock Oil Sands, Inc.)

  	
   

  	
  2,300,000

  	
   

  	
  23%

  	
   

  	
  Common

  	
   

  	
  71

  



 


 

















 


SCHEDULE II
TO PLEDGE AGREEMENT


 


Excluded Shares


 


200,000 shares of the $0.001 par value common
stock of Redrock Energy, Inc. (f.k.a. Redrock Oil Sands, Inc. and Wentworth Oil
Sands, Inc.) represented by share certificate no. 0055.


 

















 


ANNEX I


 


TO


 


PLEDGE
AGREEMENT


 


 


PLEDGE
AMENDMENT


 


This Pledge Amendment, dated •, 20•, is delivered pursuant
to Section 4 of the Amended and Restated Pledge Agreement referred to
below.  The undersigned hereby agrees
that this Pledge Amendment may be attached to the Amended and Restated Pledge
Agreement, dated as of October 31, 2007, made by Wentworth Energy, Inc. in
favor of CASTLERIGG MASTER INVESTMENTS LTD., as Collateral Agent for the Buyers
(the “Collateral Agent”), as said Amended and Restated Pledge Agreement may
heretofore have been or hereafter may be amended or otherwise modified or
supplemented from time to time and that the promissory notes [and/or] shares or
other equity interests listed on this Pledge Amendment shall be hereby pledged
and assigned to the Collateral Agent and become part of the Collateral referred
to in such Amended and Restated Pledge Agreement and shall secure all of the
Obligations referred to in such Amended and Restated Pledge Agreement.


 


Pledged
Shares


 


	
  Pledgor

  	
   

  	
  Name of
  Issuer

  	
   

  	
  Number
  of Shares or Other Equity Interests

  	
   

  	
  Class

  	
   

  	
  Certificate
  No(s)

  
	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  	
   

  



 


	
   

  	
  WENTWORTH
  ENERGY, INC.

  
	
   

  	
   

  	
   

  	
   

  
	
   

  	
  By:

  	
   

  	
   

  
	
   

  	
   

  	
  Name:

  
	
   

  	
   

  	
  Title: