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Exhibit 10.5

REGISTRATION RIGHTS AGREEMENT

        THIS REGISTRATION RIGHTS AGREEMENT (this "Agreement") is made and
entered into as of November 23, 2004, by and among Petrohawk Energy Corporation,
a Delaware corporation (the "Company"), on the one hand, and Friedman, Billings,
Ramsey & Co., Inc., a Delaware corporation ("FBR") for the benefit of the
Holders (as hereinafter defined), on the other hand.

W I T N E S S E T H:

        WHEREAS, the Company and FBR entered into that certain Placement
Agreement dated as of November 16, 2004 (the "Placement Agreement"), in
connection with which on November 23, 2004, the Company sold 2,580,645 newly
issued shares (the "Preferred Shares") of its Series B 8% Automatically
Convertible Preferred Stock, par value $0.001 per share (the "Series B Preferred
Stock"), each of which is convertible into ten shares (the "Common Shares") of
the Company's common stock, par value $0.001 (the "Common Stock"), with FBR
acting as placement agent;

        WHEREAS, in order to induce FBR to enter into the Placement Agreement,
the Company has agreed to provide the registration rights provided for in this
Agreement for the holders of Registrable Shares (as defined below); and

        WHEREAS, the execution of this Agreement is a condition to the closing
of the transactions contemplated by the Placement Agreement.

        NOW, THEREFORE, in consideration of the premises and the mutual
covenants of the parties hereto, and for other good and valuable consideration,
the receipt and sufficiency of which are hereby acknowledged, the parties hereto
hereby agree as follows:

1.    Definitions.    As used in this Agreement, the following terms shall have
the following meanings:

        "Additional Payments" is defined in Section 7(a).

        "Additional Shares" means shares or other securities issued in respect
of the Shares by reason of or in connection with any stock dividend, stock
distribution, stock split or similar issuance.

        "Agreement" is defined in the introductory paragraph of this Agreement.

        "Affiliate" means, as to any specified Person, (i) any Person that
directly, or indirectly through one or more intermediaries, controls or is
controlled by, or is under common control with, the specified Person, (ii) any
executive officer, director, trustee or general partner of the specified Person
and (iii) any legal entity for which the specified Person acts as an executive
officer, director, trustee or general partner. For purposes of this definition,
"control" (including the correlative meanings of the terms "controlled by" and
"under common control with"), as used with respect to any Person, shall mean the
possession, directly, or indirectly through one or more intermediaries, of the
power to direct or cause the direction of the management and policies of such
Person, whether by contract, through the ownership of voting securities,
partnership interests or other equity interests or otherwise.

        "Business Day" means each Monday, Tuesday, Wednesday, Thursday and
Friday that is not a day on which banking institutions in New York, New York are
authorized or obligated by applicable law, regulation or executive order to
close.

        "Closing Date" means the Closing Date as defined in the Placement
Agreement.

        "Commission" means the Securities and Exchange Commission.

        "Common Shares" is defined in the first recital clause of this
Agreement.

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        "Common Stock" is defined in the first recital clause of this Agreement.

        "Company" is defined in the introductory paragraph of this Agreement,
and any successor thereto.

        "Controlling Person" is defined in Section 6(a) hereof.

        "End of Suspension Notice" is defined in Section 5(b) hereof.

        "Exchange Act" means the Securities Exchange Act of 1934, as amended,
and the rules and regulations promulgated by the Commission pursuant thereto.

        "FBR" is defined in the introductory paragraph of this Agreement, and
any successor thereto.

        "Holder" means each record owner of any Registrable Shares from time to
time.

        "Indemnified Party" is defined in Section 6(c) hereof.

        "Indemnifying Party" is defined in Section 6(c) hereof.

        "Liabilities" is defined in Section 6(a) hereof.

        "Mandatory Registration Statement" means the Mandatory Shelf
Registration Statement or any Subsequent Shelf Registration Statement.

        "Mandatory Shelf Registration Statement" is defined in Section 2(a)
hereof.

        "NASD" means the National Association of Securities Dealers, Inc.

        "Person" means an individual, limited liability company, partnership,
corporation, trust, unincorporated organization, government or agency or
political subdivision thereof, or any other legal entity.

        "Piggyback Registration Statement" is defined in Section 2(b) hereof.

        "Placement Agreement" is defined in the first recital clause of this
Agreement.

        "Preferred Shares" is defined in the first recital clause of this
Agreement.

        "Prior Holder" means PHAWK LLC, a Delaware limited liability company,
and any other investor a party to or beneficiary of the Registration Rights
Agreement dated May            , 2004 by and among the Company and PHAWK, LLC.

        "Prospectus" means the prospectus included in any Registration
Statement, including any preliminary prospectus, and all other amendments and
supplements to any such prospectus, including post-effective amendments, and all
material incorporated by reference or deemed to be incorporated by reference, if
any, in such prospectus.

        "Purchaser Indemnitee" is defined in Section 6(a) hereof.

        "Registrable Shares" means each of (a) the Common Shares and any
Additional Shares in respect thereof, and (b) if and only if the Preferred
Shares have not automatically converted into Common Stock within 60 days after
the date hereof, the Preferred Shares and any Additional Shares in respect
thereof, in each case, upon original issuance thereof, and at all times
subsequent thereto, including upon the transfer thereof by the original holder
or any subsequent holder, until, in the case of any such Shares or Additional
Shares, as applicable, the earliest to occur of:

        (i)    the date on which they have been sold pursuant to a Registration
Statement or sold pursuant to Rule 144;

        (ii)   the date on which they are saleable, in the opinion of counsel to
the Company, without registration under the Securities Act pursuant to
Rule 144(k);

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        (iii)  the date on which they are saleable, without restriction,
pursuant to an available exemption from registration under the Securities Act;
or

        (iv)  the date on which they are sold to the Company or its
subsidiaries.

        "Registration Default" is defined in Section 7(a).

        "Registration Expenses" means any and all expenses incident to the
performance of or compliance with this Agreement, including, without limitation:
(i) all Commission, securities exchange, NASD registration, listing, inclusion
and filing fees, (ii) all fees and expenses incurred in connection with
compliance with international, federal or state securities or blue sky laws
(including, without limitation, any registration, listing and filing fees and
reasonable fees and disbursements of counsel in connection with blue sky
qualification of any of the Registrable Shares and the preparation of a blue sky
memorandum and compliance with the rules of the NASD), (iii) all expenses of any
Persons in preparing or assisting in preparing, word processing, duplicating,
printing, delivering and distributing any Registration Statement, any
Prospectus, any amendments or supplements thereto, any underwriting agreements,
securities sales agreements, certificates and any other documents relating to
the performance under and compliance with this Agreement, (iv) all fees and
expenses incurred in connection with the listing or inclusion of any of the
Registrable Shares on the NASDAQ Stock Market pursuant to Section 4(n) of this
Agreement, (v) the fees and disbursements of counsel for the Company and of the
independent public accountants of the Company (including, without limitation,
the expenses of any special audit and "cold comfort" letters required by or
incident to such performance), and (vi) any fees and disbursements customarily
paid in issues and sales of securities (including the fees and expenses of any
experts retained by the Company in connection with any Registration Statement),
provided, however, that Registration Expenses shall exclude brokers' or
underwriters' discounts and commissions and transfer taxes, if any, relating to
the sale or disposition of Registrable Shares by a Holder and the fees and
disbursements of any counsel to the Holders other than as provided for in
clause (v) above.

        "Registration Statement" means any Mandatory Registration Statement or
Piggyback Registration Statement.

        "Rule 144", "Rule 158", "Rule 415", or "Rule 424", respectively, means
such specified rule promulgated by the Commission pursuant to the Securities
Act, as such rule may be amended from time to time, or any similar rule or
regulation hereafter adopted by the Commission as a replacement thereto having
substantially the same effect as such rule.

        "Securities Act" means the Securities Act of 1933, as amended, and the
rules and regulations promulgated by the Commission thereunder.

        "Series B Preferred Stock" is defined in the first recital clause of
this Agreement.

        "Shares" means the Common Shares and the Preferred Shares.

        "Subsequent Shelf Registration Statement" is defined in Section 2(c)
hereof.

        "Suspension Event" is defined in Section 5(b) hereof.

        "Suspension Notice" is defined in Section 5(b) hereof.

        "Underwritten Offering" means a sale of securities of the Company to an
underwriter or underwriters for reoffering to the public.

2.    Registration Rights.

        (a)    Mandatory Shelf Registration.    As set forth in Section 4, the
Company agrees to file with the Commission as soon as reasonably practicable,
but in no event later than 60 days following the Closing Date, a shelf
registration statement on Form S-3 or such other form under the Securities Act
then

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available to the Company providing for the resale pursuant to Rule 415 from time
to time by the Holders of any and all Registrable Shares consisting of
(i) Common Shares and all Additional Shares in respect thereof, and (ii) if and
only if the Preferred Shares have not automatically converted into Common Stock
within 60 days after the date hereof, the Preferred Shares and all Additional
Shares issued in respect thereof (in each case including for the avoidance of
doubt any Additional Shares that are issued prior to the effectiveness of such
shelf registration statement) (including the Prospectus, amendments and
supplements to such registration statement or Prospectus, including pre- and
post-effective amendments, all exhibits thereto and all material incorporated by
reference or deemed to be incorporated by reference, if any, in such
registration statement, the "Mandatory Shelf Registration Statement"). The fact
that the Preferred Shares have not converted into Common Stock within such
60-day period shall not affect the Company's continuing obligation to use its
best efforts to cause such conversion or to register the sale of such shares
hereunder.

        (i)    Effectiveness and Scope.    The Company shall use its
commercially reasonable efforts to cause any Mandatory Registration Statement to
be declared effective by the Commission as soon as reasonably practicable
following such filing, and to remain effective until the earlier of (A) the
second anniversary of the effective date of the initial Mandatory Shelf
Registration Statement (subject to extension pursuant to Section 5(c)) (provided
that in such case each Holder shall have received a certificate with all
restrictive legends removed as a result of the applicable Registrable Shares
being freely transferable under Rule 144(k)), or (B) the date on which all
Shares and any Additional Shares in respect thereof cease to be Registrable
Shares. The Company may include any shares of Common Stock owned by a Prior
Holder in a Mandatory Shelf Registration Statement. Any Mandatory Shelf
Registration Statement shall provide for the resale from time to time, and
pursuant to any method or combination of methods legally available (including,
without limitation, an Underwritten Offering, a direct sale to purchasers, a
sale through brokers or agents, or a sale over the internet) by the Holders of
any and all Registrable Shares.

        (ii)    Underwriting.    If any Holder proposes to conduct an
Underwritten Offering under a Mandatory Shelf Registration Statement, such
Holder shall advise the Company, all other Holders, and any Prior Holders whose
securities are included in the Mandatory Shelf Registration Statement, of the
managing underwriters for such proposed Underwritten Offering, such managing
underwriters to be subject to the approval of the Company, not to be
unreasonably withheld. In such event, the Company shall enter into an
underwriting agreement in customary form with the managing underwriters, which
shall include, among other provisions, indemnities to the effect and to the
extent provided in Section 6, and shall take all such other reasonable actions
as are requested by the managing underwriter in order to expedite or facilitate
the registration and disposition of the Registrable Shares included in such
Underwritten Offering; provided, however, that the Company shall be required to
cause appropriate officers of the Company or its Affiliates to participate in a
"road show" or similar marketing effort being conducted by such underwriter with
respect to such Underwritten Offering only if the Holders reasonably anticipate
gross proceeds from such Underwritten Offering of at least $20 million. All
Holders proposing to distribute their Registrable Shares through such
Underwritten Offering and, if a Prior Holder elects to distribute its shares of
Common Stock through such Underwritten Offering, such Prior Holder, shall enter
into an underwriting agreement in customary form with the managing underwriters
selected for such underwriting and complete and execute any questionnaires,
powers of attorney, indemnities, securities escrow agreements and other
documents reasonably required under the terms of such underwriting, and furnish
to the Company such information in writing as the Company may reasonably request
for inclusion in the Registration Statement; provided, however, that neither any
Holder nor any Prior Holder shall be required to make any representations or
warranties to or agreements with the Company or the underwriters other than
representations, warranties or agreements as are customary and reasonably
requested by the underwriters. Notwithstanding any other provision of this
Agreement, if the managing underwriters

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determine in good faith that marketing factors require a limitation on the
number of shares to be included in such Underwritten Offering, then the managing
underwriters may exclude shares (including Registrable Shares) from the
Underwritten Offering, and any shares included in the Underwritten Offering
shall be allocated first, to each of the Holders requesting inclusion of their
Registrable Shares in such Underwritten Offering on a pro rata basis based on
the total number of Registrable Shares then held by each such Holder which is
requesting inclusion, and second, to any Prior Holders requesting inclusion of
their shares in such Underwritten Offering.

        (iii)    Selling Stockholder Questionnaires.    Each Holder agrees, by
its acquisition of Registrable Shares, that if such Holder wishes to sell
Registrable Shares pursuant to the Mandatory Shelf Registration Statement and
related Prospectus, it will do so only in accordance with this
Section 2(a)(iii). Each Holder wishing to sell Registrable Shares pursuant to a
Mandatory Shelf Registration Statement and related Prospectus agrees to deliver
a written notice, substantially in form and substance of Annex A (a "Notice and
Questionnaire"), to the Company. The Company shall mail the Notice and
Questionnaire to the Holders no later than the date of initial filing of the
Mandatory Shelf Registration Statement with the Commission. No Holder shall be
entitled to be named as a selling securityholder in the Mandatory Shelf
Registration Statement as of the initial effective date of the Mandatory Shelf
Registration Statement, and no Holder shall be entitled to use the Prospectus
forming a part thereof for resales of Registrable Shares at any time, unless
such Holder has returned a completed and signed Notice and Questionnaire to the
Company by the deadline for response set forth therein; provided, however,
Holders shall have at least 20 calendar days from the date on which the Notice
and Questionnaire is first mailed to such Holders to return a completed and
signed Notice and Questionnaire to the Company. Notwithstanding the foregoing,
(x) upon the request of any Holder that did not return a Notice and
Questionnaire on a timely basis or did not receive a Notice and Questionnaire
because it was a subsequent transferee of Registrable Shares after the Company
mailed the Notice and Questionnaire, the Company shall distribute a Notice and
Questionnaire to such Holders at the address set forth in the request and
(y) upon receipt of a properly completed Notice and Questionnaire from such
Holder, the Company shall use all commercially reasonable efforts to name such
Holder as a selling securityholder in the Mandatory Shelf Registration Statement
by means of a pre-effective amendment, by means of a post-effective amendment
or, if permitted by the Commission, by means of a Prospectus supplement to the
Mandatory Shelf Registration Statement; provided, however, that the Company will
have no obligation to add Holders to the Shelf Mandatory Registration Statement
as selling securityholders more frequently that one time per every 30 calendar
days.

        (b)    Piggyback Registration.    If, after the date hereof, the Company
proposes to file a registration statement under the Securities Act providing for
a public offering of the Company's securities, other than a registration
statement on Form S-8 or Form S-4 or any similar form hereafter adopted by the
Commission as a replacement therefor (including the Prospectus, amendments and
supplements to such registration statement or Prospectus, including pre- and
post-effective amendments, all exhibits thereto and all material incorporated by
reference or deemed to be incorporated by reference, if any, in such
registration statement, the "Piggyback Registration Statement"), the Company
will notify each Holder of the proposed filing and afford each Holder an
opportunity to include in such Piggyback Registration Statement all or any part
of the Registrable Shares then held by such Holder. Each Holder desiring to
include in any such Piggyback Registration Statement all or part of the
Registrable Shares held by such Holder shall, within ten (10) days after
delivery of the above-described notice by the Company, so notify the Company in
writing, and in such notice shall inform the Company of the number of
Registrable Shares such Holder wishes to include in such Piggyback Registration
Statement and provide, as a condition to such inclusion, such information
regarding itself, the Registrable Shares held by it and the intended method of
disposition of such securities as is required pursuant to Regulation S-K
promulgated under the Securities Act to effect the registration of the
Registrable

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Shares. Any election by any Holder to include any Registrable Shares in such
Piggyback Registration Statement will not affect the inclusion of such
Registrable Shares in the Mandatory Shelf Registration Statement until such
Registrable Shares have been sold under the Piggyback Registration Statement;
provided, however, that at such time, the Company shall have the right to remove
from the Mandatory Shelf Registration Statement the Registrable Shares sold
pursuant to the Piggyback Registration Statement.

        (i)    Right to Terminate Piggyback Registration.    At any time, the
Company may terminate or withdraw any Piggyback Registration Statement referred
to in this Section 2(b), and without any obligation to any such Holder whether
or not any Holder has elected to include Registrable Shares in such
registration. The Company shall also have the right to suspend the effectiveness
and use of any Piggyback Registration Statement at any time for an unlimited
amount of time whether or not any Holder has elected to include Registrable
Shares in such registration.

        (ii)    Underwriting.    The Company shall advise the Holders of the
managing underwriters for any Underwritten Offering proposed under the Piggyback
Registration Statement. The right of any such Holder's Registrable Shares to be
included in any Piggyback Registration Statement pursuant to this Section 2(b)
shall be conditioned upon such Holder's participation in such Underwritten
Offering and the inclusion of such Holder's Registrable Shares in the
Underwritten Offering to the extent provided herein. All Holders proposing to
distribute their Registrable Shares through such Underwritten Offering shall
enter into an underwriting agreement in customary form with the managing
underwriters selected for such underwriting and complete and execute any
questionnaires, powers of attorney, indemnities, securities escrow agreements
and other documents reasonably required under the terms of such underwriting,
and furnish to the Company such information in writing as the Company may
reasonably request for inclusion in the Registration Statement; provided,
however, that no Holder shall be required to make any representations or
warranties to or agreements with the Company or the underwriters other than
representations, warranties or agreements as are customary and reasonably
requested by the underwriters. Notwithstanding any other provision of this
Agreement, if the managing underwriters determine in good faith that marketing
factors require a limitation on the number of shares to be included, then the
managing underwriters may exclude shares (including Registrable Shares) from the
Piggyback Registration Statement and the Underwritten Offering, and any Shares
included in the Piggyback Registration Statement and the Underwritten Offering
shall be allocated, first, to the Company, and second, to each of the Holders
and the Prior Holder(s) requesting inclusion of their Registrable Shares in such
Piggyback Registration Statement on a pro rata basis based on the total number
of Registrable Shares then held by each such Holder which is requesting
inclusion. If any Holder disapproves of the terms of any Underwritten Offering,
such Holder may elect to withdraw therefrom by written notice to the Company and
the underwriter, delivered at least 10 Business Days prior to the effective date
of the Piggyback Registration Statement. Any Registrable Shares excluded or
withdrawn from such Underwritten Offering shall be excluded and withdrawn from
the Piggyback Registration Statement.

        (iii)    Hold-Back Agreement.    By electing to include Registrable
Shares in the Piggyback Registration Statement, if any, the Holder shall be
deemed to have agreed not to effect any sale or distribution of securities of
the Company of the same or similar class or classes of the securities included
in the Registration Statement or any securities convertible into or exchangeable
or exercisable for such securities, including a sale pursuant to Rule 144 under
the Securities Act, during such periods as reasonably requested (but in no event
for a period longer than 60 days following the effective date of the Piggyback
Registration Statement, provided each of the executive officers and directors of
the Company that hold shares of Common Stock of the Company or securities
convertible into or exchangeable or exercisable for shares of Common Stock

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of the Company are subject to the same restriction for the entire time period
required of the Holders hereunder) by the representatives of the underwriters,
if an Underwritten Offering.

        (iv)    Mandatory Shelf Registration not Impacted by Piggyback
Registration Statement.    The Company's obligation to file any Mandatory Shelf
Registration Statement shall not be affected by the filing or effectiveness of
the Piggyback Registration Statement.

        (c)    Subsequent Shelf Registration for Additional Shares Issued after
Effectiveness of the Mandatory Shelf Registration Statement.    If any
Additional Shares are issued or distributed to Holders after the effectiveness
of the Mandatory Shelf Registration Statement, or such Additional Shares were
otherwise not included in a prior Registration Statement, then the Company shall
as soon as practicable file an additional shelf registration statement
(including the Prospectus, amendments and supplements to such registration
statement or Prospectus, including pre- and post-effective amendments, all
exhibits thereto and all material incorporated by reference or deemed to be
incorporated by reference, if any, in such registration statement, a "Subsequent
Shelf Registration Statement") covering such Additional Shares on behalf of the
Holders thereof in the same manner, and subject to the same provisions in this
Agreement as the Mandatory Shelf Registration Statement.

        (d)    Expenses.    The Company shall pay all Registration Expenses in
connection with the registration of the Registrable Shares pursuant to this
Agreement. Each Holder participating in a registration pursuant to this
Section 2 shall bear such Holder's proportionate share (based on the total
number of Registrable Shares sold in such registration) of all discounts and
commissions payable to underwriters or brokers and all transfer taxes in
connection with a registration of Registrable Shares pursuant to this Agreement
and any other expense of the Holders not specifically allocated to the Company
pursuant to this Agreement relating to the sale or disposition of such Holder's
Registrable Shares pursuant to any Registration Statement.

3.    Rule 144 Reporting.

        With a view to making available the benefits of certain rules and
regulations of the Commission that may permit the sale of the Registrable Shares
to the public without registration, the Company agrees to, so long as any Holder
owns any Registrable Shares:

        (a)   make and keep public information available, as those terms are
understood and defined in Rule 144(c) under the Securities Act;

        (b)   use its commercially reasonable efforts to file with the
Commission in a timely manner all reports and other documents required to be
filed by the Company under the Securities Act and the Exchange Act; and

        (c)   furnish to any Holder promptly upon request a written statement by
the Company as to its compliance in all material respects with the reporting
requirements of Rule 144 and of the Exchange Act, a copy of the most recent
annual or quarterly report of the Company, and such other reports and documents
of the Company, and take such reasonable further actions consistent with this
Section 3, as a Holder may reasonably request in availing itself of any rule or
regulation of the Commission allowing a Holder to sell any such Registrable
Shares without registration.

4.    Registration Procedures.

        In connection with the obligations of the Company with respect to any
registration pursuant to this Agreement, the Company shall:

        (a)   prepare and file with the Commission, as specified in this
Agreement, each Registration Statement, which Registration Statement shall
comply as to form in all material respects with the requirements of the
applicable form and include all financial statements required by the Commission
to be filed therewith, and use its commercially reasonable efforts to cause any
Mandatory Registration

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Statement to become and remain effective as set forth in Section 2(a)(i) hereof;
provided, however, that the Company shall not be required to cause any Piggyback
Registration Statement to become or remain effective;

        (b)   subject to Section 4(i) hereof, (i) prepare and file with the
Commission such amendments and post-effective amendments to each such
Registration Statement as may be necessary to keep such Registration Statement
effective for the period described in Section 4(a) hereof, (ii) cause each
Prospectus contained therein to be supplemented by any required Prospectus
supplement, and as so supplemented to be filed pursuant to Rule 424 or any
similar rule that may be adopted under the Securities Act, and (iii) comply in
all material respects with the provisions of the Securities Act with respect to
the disposition of all securities covered by each Registration Statement during
the applicable period in accordance with the intended method or methods of
distribution by the selling Holders thereof;

        (c)   furnish to the Holders, without charge, as many copies of each
Prospectus, including each preliminary Prospectus, and any amendment or
supplement thereto and such other documents as such Holder may reasonably
request, in order to facilitate the public sale or other disposition of the
Registrable Shares; the Company hereby consenting to the use of such Prospectus,
including each preliminary Prospectus, by the Holders, if any, in connection
with the offering and sale of the Registrable Shares covered by any such
Prospectus;

        (d)   use its commercially reasonable efforts to register or qualify, or
obtain exemption from registration or qualification for, all Registrable Shares
by the time the applicable Registration Statement is declared effective by the
Commission under all applicable state securities or "blue sky" laws of such
domestic jurisdictions as FBR or any Holder covered by a Registration Statement
shall reasonably request in writing, keep each such registration or
qualification or exemption effective during the period such Registration
Statement is required to be kept effective pursuant to Section 4(a) and do any
and all other acts and things that may be reasonably necessary or advisable to
enable such Holder to consummate the disposition in each such jurisdiction of
such Registrable Shares owned by such Holder; provided, however, that the
Company shall not be required to (i) qualify generally to do business in any
jurisdiction or to register as a broker or dealer in such jurisdiction where it
would not otherwise be required to qualify but for this Section 4(d),
(ii) subject itself to taxation in any such jurisdiction, or (iii) submit to the
general service of process in any such jurisdiction;

        (e)   use its commercially reasonable efforts to cause all Registrable
Shares covered by such Registration Statement to be registered and approved by
such other domestic governmental agencies or authorities, if any, as may be
necessary to enable the Holders thereof to consummate the disposition of such
Registrable Shares;

        (f)    notify FBR and each Holder with Registrable Shares covered by a
Registration Statement promptly and, if requested by FBR or any such Holder,
confirm such advice in writing (i) when such Registration Statement has become
effective and when any post-effective amendments and supplements thereto become
effective, (ii) of the issuance by the Commission or any state securities
authority of any stop order suspending the effectiveness of such Registration
Statement or the initiation of any proceedings for that purpose, (iii) of any
request by the Commission or any other federal or state governmental authority
for amendments or supplements to such Registration Statement or related
Prospectus or for additional information, and (iv) of the happening of any event
during the period such Registration Statement is effective as a result of which
such Registration Statement or the related Prospectus or any document
incorporated by reference therein contains any untrue statement of a material
fact or omits to state any material fact required to be stated therein or
necessary to make the statements therein not misleading (which information shall
be accompanied by an instruction to suspend the use of the Registration
Statement and the Prospectus until the requisite changes have been made);

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        (g)   during the period of time referred to in Section 4(a) above, use
its commercially reasonable efforts to avoid the issuance of, or if issued, to
obtain the withdrawal of, any order enjoining or suspending the use or
effectiveness of a Registration Statement or suspending the qualification (or
exemption from qualification) of any of the Registrable Shares for sale in any
jurisdiction, as promptly as practicable;

        (h)   upon request, furnish to each requesting Holder with Registrable
Shares covered by a Registration Statement, without charge, at least one
conformed copy of such Registration Statement and any post-effective amendment
or supplement thereto (without documents incorporated therein by reference or
exhibits thereto, unless requested);

        (i)    except as provided in Section 5, upon the occurrence of any event
contemplated by Section 4(f)(iv), use its commercially reasonable efforts to
promptly prepare a supplement or post-effective amendment to a Registration
Statement or the related Prospectus or any document incorporated therein by
reference or file any other required document so that, as thereafter delivered
to the purchasers of the Registrable Shares, such Prospectus will not contain
any untrue statement of a material fact or omit to state a material fact
required to be stated therein or necessary to make the statements therein, in
the light of the circumstances under which they were made, not misleading, and,
upon request, promptly furnish to each requesting Holder a reasonable number of
copies of each such supplement or post-effective amendment;

        (j)    if requested by the representative of the underwriters, if any,
or any Holders of Registrable Shares being sold in connection with an
Underwritten Offering, (i) promptly incorporate in a Prospectus supplement or
post-effective amendment such material information as the representative of the
underwriters, if any, or such Holders indicate relates to them or otherwise
reasonably request be included therein and (ii) make all required filings of
such Prospectus supplement or such post-effective amendment as soon as
practicable after the Company has received notification of the matters to be
incorporated in such Prospectus supplement or post-effective amendment;

        (k)   in the case of an Underwritten Offering, use its commercially
reasonable efforts to furnish or caused to be furnished to each Holder of
Registrable Shares covered by such Registration Statement and the underwriters a
signed counterpart, addressed to each such Holder and the underwriters, of:
(i) an opinion of counsel for the Company, dated the date of each closing under
the underwriting agreement, reasonably satisfactory to the underwriters; and
(ii) a "comfort" letter, dated the effective date of such Registration Statement
and the date of each closing under the underwriting agreement, signed by the
independent public accountants who have certified the Company's financial
statements included in such Registration Statement, covering substantially the
same matters with respect to such Registration Statement (and the Prospectus
included therein) and with respect to events subsequent to the date of such
financial statements, as are customarily covered in accountants' letters
delivered to underwriters in underwritten public offerings of securities, and
such other financial matters as the underwriters may reasonably request and
customarily obtained by underwriters in underwritten offerings; provided that,
in order to be an addressee of the comfort letter, each Holder may be required
to confirm that it is in the category of persons to whom a comfort letter may be
delivered in accordance with applicable accounting literature;

        (l)    enter into customary agreements (including in the case of an
Underwritten Offering, an underwriting agreement in customary form) and take all
other action in connection therewith in order to expedite or facilitate the
distribution of the Registrable Shares included in such Registration Statement
and, in the case of an Underwritten Offering, make representations and
warranties to the underwriters in such form and scope as are customarily made by
issuers to underwriters in underwritten offerings consistent with
representations and warranties made by the Company in public or private
offerings and confirm the same to the extent customary if and when requested;

9

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        (m)  in connection with an Underwritten Offering, use its commercially
reasonable efforts to make available for inspection by the representative of any
underwriters participating in any disposition pursuant to a Registration
Statement, all financial and other records, pertinent corporate documents and
properties of the Company and cause the respective officers, directors and
employees of the Company to supply all information reasonably requested by any
such representatives, the representative of the underwriters, counsel thereto or
accountants in connection with a Registration Statement; provided, however, that
such records, documents or information that the Company determines, in good
faith, to be confidential and notifies such representatives, representative of
the underwriters, counsel thereto or accountants are confidential shall not be
disclosed by the representatives, representative of the underwriters, counsel
thereto or accountants unless (i) the disclosure of such records, documents or
information is necessary to avoid or correct a misstatement or omission in a
Registration Statement or Prospectus, (ii) the release of such records,
documents or information is ordered pursuant to a subpoena or other order from a
court of competent jurisdiction, or (iii) such records, documents or information
have been generally made available to the public; provided further, that to the
extent practicable, the foregoing inspection and information gathering shall be
coordinated on behalf of the Holders and the other parties entitled thereto by
one counsel designated by and on behalf of the Holders and the other parties,
which counsel the Company determines in good faith is reasonably acceptable;

        (n)   use its commercially reasonable efforts (including, without
limitation, seeking to cure in the Company's listing or inclusion application
any deficiencies cited by the exchange or market) to list or include all
Registrable Shares on any securities exchange or the Nasdaq Stock Market on
which the Common Stock is then listed or included;

        (o)   prepare and file in a timely manner all documents and reports
required by the Exchange Act and, to the extent the Company's obligation to file
such reports pursuant to Section 15(d) of the Exchange Act expires prior to the
expiration of the effectiveness period of the Registration Statement as required
by Section 4(a) hereof, the Company shall register the Registrable Shares under
the Exchange Act and shall maintain such registration through the effectiveness
period required by Section 4(a) hereof;

        (p)   (i) otherwise use its commercially reasonable efforts to comply in
all material respects with all applicable rules and regulations of the
Commission, (ii) make generally available to its stockholders, as soon as
reasonably practicable, earnings statements covering at least 12 months that
satisfy the provisions of Section 11(a) of the Securities Act and Rule 158
thereunder, and (iii) delay filing any Registration Statement or Prospectus or
amendment or supplement to such Registration Statement or Prospectus to which
any Holder of Registrable Shares covered by any Registration Statement shall
have reasonably objected on the grounds that such Registration Statement or
Prospectus or amendment or supplement does not comply in all material respects
with the requirements of the Securities Act, such Holder having been furnished
with a copy thereof at least two Business Days prior to the filing thereof,
provided that the Company may file such Registration Statement or Prospectus or
amendment or supplement following such time as the Company shall have made a
good faith effort to resolve any such issue with the objecting Holder and shall
have advised the Holder in writing of its reasonable belief that such filing
complies in all material respects with the requirements of the Securities Act;

        (q)   cause to be maintained a registrar and transfer agent for all
Registrable Shares covered by any Registration Statement from and after a date
not later than the effective date of such Registration Statement; and

        (r)   in connection with any sale or transfer of the Registrable Shares
(whether or not pursuant to a Registration Statement) that will result in the
securities being delivered no longer constituting Registrable Shares, cooperate
with the Holders and the representative of the underwriters, if any, to
facilitate the timely preparation and delivery of certificates representing the
Registrable Shares to be

10

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sold, which certificates shall not bear any transfer restrictive legends (other
than as required by the Company's charter), and to enable such Registrable
Shares to be in such denominations and registered in such names as the
representative of the underwriters, if any, or the Holders may request at least
three Business Days prior to any sale of the Registrable Shares.

        The Company may require the Holders to furnish to the Company such
information regarding the proposed distribution by such Holder as the Company
may from time to time reasonably request in writing or as shall be required to
effect the registration of the Registrable Shares, and no Holder shall be
entitled to be named as a selling stockholder in any Registration Statement and
no Holder shall be entitled to use the Prospectus forming a part thereof if such
Holder does not provide such information to the Company. Each Holder further
agrees to furnish promptly to the Company in writing all information required
from time to time to make the information previously furnished by such Holder
not misleading.

        Each Holder agrees that, upon receipt of any notice from the Company of
the happening of any event of the kind described in Section 4(f)(ii),
4(f)(iii) or 4(f)(iv) hereof, such Holder will immediately discontinue
disposition of Registrable Shares pursuant to a Registration Statement until
(i) any such stop order is vacated or (ii) if an event described in
Section 4(f)(iii) or 4(f)(iv) occurs, such Holder's receipt of the copies of the
supplemented or amended Prospectus. If so directed by the Company, such Holder
will deliver to the Company (at the reasonable expense of the Company) all
copies in its possession, other than permanent file copies then in such Holder's
possession, of the Prospectus covering such Registrable Shares current at the
time of receipt of such notice.

5.    Suspension Period.

        (a)   Subject to the provisions of this Section 5 and a good faith
determination by a majority of the Board of Directors of the Company that it is
in the best interests of the Company to suspend the use of any Mandatory
Registration Statement, following the effectiveness of such Mandatory
Registration Statement (and the filings with any international, federal or state
securities commissions), the Company, by written notice to FBR and the Holders,
may direct the Holders to suspend sales of the Registrable Shares pursuant to
such Mandatory Registration Statement for such times as the Company reasonably
may determine is necessary and advisable (but in no event for more than 45 days
in any 90-day period or more than 60 days in any 12-month period), if any of the
following events shall occur: pending discussions relating to, or the
consummation of, a transaction or the occurrence of an event (x) that would
require additional disclosure of material information by the Company in the
Mandatory Registration Statement (or such filings) and which has not been so
disclosed, (y) as to which the Company has a bona fide business purpose for
preserving confidentiality, or (z) that renders the Company unable to comply
with Commission requirements, in each case under circumstances that would make
it impractical or inadvisable to promptly amend or supplement the Mandatory
Registration Statement on a post-effective basis, as applicable. Upon the
earlier to occur of (i) the Company delivering to the Holders and FBR an End of
Suspension Notice, as hereinafter defined, or (ii) the end of the maximum
permissible suspension period, the Company shall use its commercially reasonable
efforts to promptly amend or supplement the Mandatory Registration Statement on
a post-effective basis, if necessary, or to take such action as is necessary to
make resumed use of the Mandatory Registration Statement compatible with the
Company's best interests, as applicable, so as to permit the Holders to resume
sales of the Registrable Shares as soon as possible. The Company shall have the
right to suspend the effectiveness and use of any Piggyback Registration
Statement at any time for an unlimited amount of time.

        (b)   In the case of an event that causes the Company to suspend the use
of a Registration Statement (a "Suspension Event"), the Company shall give
written notice (a "Suspension Notice") to the Holders to suspend sales of the
Registrable Shares, and such notice shall state that such suspension shall
continue only for so long as the Suspension Event or its effect is continuing
and the Company is

11

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taking all reasonable steps to terminate suspension of the effectiveness of the
Registration Statement as promptly as possible. The Holders shall not effect any
sales of the Registrable Shares pursuant to such Registration Statement (or such
filings) at any time after it has received a Suspension Notice from the Company
and prior to receipt of an End of Suspension Notice (as defined below). If so
directed by the Company, each Holder will deliver to the Company (at the expense
of the Company) all copies other than permanent file copies then in such
Holder's possession of the Prospectus covering the Registrable Shares at the
time of receipt of the Suspension Notice. The Holders may recommence effecting
sales of the Registrable Shares pursuant to the Registration Statement (or such
filings) following further notice to such effect (an "End of Suspension Notice")
from the Company, which End of Suspension Notice shall be given by the Company
to the Holders and FBR in the manner described above promptly following the
conclusion of any Suspension Event and its effect.

        (c)   Notwithstanding any provision herein to the contrary, if the
Company shall give a Suspension Notice pursuant to this Section 5 with respect
to any Mandatory Registration Statement, the Company agrees that it shall extend
the period of time during which such Mandatory Registration Statement shall be
maintained effective pursuant to this Agreement by the number of days during the
period from the date of the giving of the Suspension Notice to and including the
date when Holders shall have received the End of Suspension Notice and copies of
the supplemented or amended Prospectus necessary to resume sales; provided such
period of time shall not be extended beyond the date that Shares or Additional
Shares are not Registrable Shares.

6.    Indemnification and Contribution.

        (a)   The Company agrees to indemnify and hold harmless (i) FBR and each
Holder, (ii) each Person, if any, who controls (within the meaning of Section 15
of the Securities Act or Section 20(a) of the Exchange Act) any of the foregoing
(a "Controlling Person"), and (iii) the respective officers, directors,
partners, members, employees, representatives and agents of FBR and each Holder
or any Controlling Person (any Person referred to in clause (i), (ii) or
(iii) may hereinafter be referred to as an "Purchaser Indemnitee") from and
against any and all losses, claims, damages, judgments, actions, reasonable
out-of-pocket expenses, and other liabilities (the "Liabilities"), including,
without limitation and as incurred, reimbursement of all reasonable costs of
investigating, preparing, pursuing or defending any claim or action, or any
investigation or proceeding by any governmental agency or body, commenced or
threatened, including the reasonable fees and expenses of outside counsel to any
Purchaser Indemnitee, joint or several, directly or indirectly related to, based
upon, arising out of or in connection with any untrue statement or alleged
untrue statement of a material fact contained in any Registration Statement or
Prospectus (as amended or supplemented if the Company shall have furnished to
such Purchaser Indemnitee any amendments or supplements thereto), or any
preliminary Prospectus or any other document prepared by the Company used to
sell the Registrable Shares, or any omission or alleged omission to state
therein a material fact required to be stated therein or necessary to make the
statements therein (in the case of a Prospectus, in light of the circumstances
under which they were made), not misleading, except insofar as such Liabilities
arise out of or are based upon (i) any untrue statement or omission or alleged
untrue statement or omission made in reliance upon and in conformity with
information relating to any Purchaser Indemnitee furnished to the Company or any
underwriter in writing by such Purchaser Indemnitee expressly for use therein,
(ii) any untrue statement contained in or omission from a preliminary Prospectus
if a copy of the Prospectus (as then amended or supplemented, if the Company
shall have furnished to or on behalf of the Holder participating in the
distribution relating to the relevant Registration Statement any amendments or
supplements thereto) was not sent or given by or on behalf of such Holder to the
Person asserting any such Liabilities who purchased Shares, if such Prospectus
(or Prospectus as amended or supplemented) is required by law to be sent or
given at or prior to the written confirmation of the sale of such Shares to such
Person and the untrue statement contained in or omission from such preliminary
Prospectus was corrected in the Prospectus (or the Prospectus as amended or
supplemented), or (iii) any sales by

12

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any Holder after the delivery by the Company to such Holder of a Suspension
Notice and before the delivery by the Company of an End of Suspension Notice.
The indemnity provided for herein shall remain in full force and effect
regardless of any investigation made by or on behalf of any Purchaser
Indemnitee.

        (b)   In connection with any Registration Statement in which a Holder is
participating, such Holder agrees, severally and not jointly, to indemnify and
hold harmless FBR, the Company, each Person who controls the Company or FBR
within the meaning of Section 15 of the Securities Act or Section 20(a) of the
Exchange Act, and the respective officers, directors, partners, members,
representatives, employees and agents of such Person or Controlling Person to
the same extent as the foregoing indemnity from the Company to each Purchaser
Indemnitee, but only with reference to (i) untrue statements or omissions or
alleged untrue statements or omissions made in reliance upon and in strict
conformity with information relating to such Holder furnished to the Company in
writing by such Holder expressly for use in any Registration Statement or
Prospectus, any amendment or supplement thereto, or any preliminary Prospectus
and (ii) any sales by any Holder after the delivery by the Company to such
Holder of a Suspension Notice and before the delivery by the Company of an End
of Suspension Notice. The liability of any Holder pursuant to clause (i) of the
immediately preceding sentence shall in no event exceed the net proceeds
received by such Holder from sales of Registrable Shares giving rise to such
obligations. If the Holder elects to include Registrable Shares in an
Underwritten Offering, the Holder shall be required to agree to such customary
indemnification provisions as may reasonably be required by the underwriter in
connection with such Underwritten Offering.

        (c)   If any suit, action, proceeding (including any governmental or
regulatory investigation), claim or demand shall be brought or asserted against
any Person in respect of which indemnity may be sought pursuant to Section 6(a)
or 6(b), such Person (the "Indemnified Party"), shall promptly notify the Person
against whom such indemnity may be sought (the "Indemnifying Party"), in writing
of the commencement thereof (but the failure to so notify an Indemnifying Party
shall not relieve it from any liability which it may have under this Section 6,
except to the extent the Indemnifying Party is materially prejudiced by the
failure to give notice), and the Indemnifying Party, upon request of the
Indemnified Party, shall retain counsel reasonably satisfactory to the
Indemnified Party to represent the Indemnified Party and any others the
Indemnifying Party may reasonably designate in such proceeding and shall assume
the defense of such proceeding and pay the fees and expenses actually incurred
by such counsel related to such proceeding. Notwithstanding the foregoing, in
any such proceeding, any Indemnified Party shall have the right to retain its
own counsel, but the fees and expenses of such counsel shall be at the expense
of such Indemnified Party, unless (i) the Indemnifying Party and the Indemnified
Party shall have mutually agreed in writing to the contrary, (ii) the
Indemnifying Party failed within a reasonable time after notice of commencement
of the action to assume the defense and employ counsel reasonably satisfactory
to the Indemnified Party, (iii) the Indemnifying Party and its counsel do not
pursue in a reasonable manner the defense of such action or (iv) the named
parties to any such action (including any impleaded parties) include both such
Indemnified Party and the Indemnifying Party, or any affiliate of the
Indemnifying Party, and such Indemnified Party shall have been reasonably
advised by counsel that, either (x) there may be one or more legal defenses
available to it which are different from or additional to those available to the
Indemnifying Party or such affiliate of the Indemnifying Party or (y) a conflict
may exist between such Indemnified Party and the Indemnifying Party or such
affiliate of the Indemnifying Party, in which event the Indemnifying Party shall
not have the right to assume or direct the defense of such action on behalf of
such Indemnified Party, it being understood, however, that the Indemnifying
Party shall not, in connection with any one such action or separate but
substantially similar or related actions arising out of the same general
allegations or circumstances, be liable for the fees and expenses of more than
one separate firm of attorneys (in addition to any local counsel) for all such
Indemnified Parties, which firm shall be designated in writing by those
Indemnified Parties who sold a majority of the Registrable Shares sold

13

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by all such Indemnified Parties and any such separate firm for the Company, the
directors, the officers and such control Persons of the Company as shall be
designated in writing by the Company. The Indemnifying Party shall not be liable
for any settlement of any proceeding effected without its written consent, which
consent shall not be unreasonably withheld or delayed, but if settled with such
consent or if there be a final judgment for the plaintiff, the Indemnifying
Party agrees to indemnify any Indemnified Party from and against any loss or
liability by reason of such settlement or judgment to the extent provided in
this Section 6 without reference to this sentence. No Indemnifying Party shall,
without the prior written consent of the Indemnified Party, effect any
settlement of any pending or threatened proceeding in respect of which any
Indemnified Party is or could have been a party and indemnity could have been
sought hereunder by such Indemnified Party, unless such settlement includes an
unconditional release of such Indemnified Party from all liability on claims
that are the subject matter of such proceeding.

        (d)   If the indemnification provided for in Section 6(a) or 6(b) is for
any reason held to be unavailable to an Indemnified Party in respect of any
Liabilities referred to therein (other than by reason of the exceptions provided
therein) or is insufficient to hold harmless a party indemnified thereunder,
then each Indemnifying Party under such sections, in lieu of indemnifying such
Indemnified Party thereunder, shall contribute to the amount paid or payable by
such Indemnified Party as a result of such Liabilities (i) in such proportion as
is appropriate to reflect the relative benefits of the Indemnified Party on the
one hand and the Indemnifying Parties on the other in connection with the
statements or omissions that resulted in such Liabilities, or (ii) if the
allocation provided by clause (i) above is not permitted by applicable law, in
such proportion as is appropriate to reflect not only the relative benefits
referred to in clause (i) above but also the relative fault of the Indemnifying
Parties and the Indemnified Party, as well as any other relevant equitable
considerations. The relative fault of the Company, on the one hand, and any
Purchaser Indemnitees, on the other, shall be determined by reference to, among
other things, whether the untrue or alleged untrue statement of a material fact
or the omission or alleged omission to state a material fact relates to
information supplied by the Company or by such Purchaser Indemnitees and the
parties' relative intent, knowledge, access to information and opportunity to
correct or prevent such statement or omission.

        (e)   The parties agree that it would not be just and equitable if
contribution pursuant to this Section 6 were determined by pro rata allocation
(even if such Indemnified Parties were treated as one entity for such purpose),
or by any other method of allocation that does not take account of the equitable
considerations referred to in Section 6(d). The amount paid or payable by an
Indemnified Party as a result of any Liabilities referred to in Section 6(d)
shall be deemed to include, subject to the limitations set forth above, any
reasonable legal or other expenses actually incurred by such Indemnified Party
in connection with investigating or defending any such action or claim.
Notwithstanding the provisions of this Section 6, in no event shall a Purchaser
Indemnitee be required to contribute any amount in excess of the amount by which
proceeds received by such Purchaser Indemnitee from sales of Registrable Shares
exceeds the amount of any damages that such Purchaser Indemnitee has otherwise
been required to pay by reason of such untrue or alleged untrue statement or
omission or alleged omission. For purposes of this Section 6, each Person, if
any, who controls (within the meaning of Section 15 of the Act or Section 20(a)
of the Exchange Act) FBR or a Holder shall have the same rights to contribution
as FBR or such Holder, as the case may be, and each Person, if any, who controls
(within the meaning of Section 15 of the Act or Section 20(a) of the Exchange
Act) the Company, and each officer, director, partner, member, employee,
representative, agent or manager of the Company shall have the same rights to
contribution as the Company. Any party entitled to contribution will, promptly
after receipt of notice of commencement of any action, suit or proceeding
against such party in respect of which a claim for contribution may be made
against another party or parties, notify each party or parties from whom
contribution may be sought, but the omission to so notify such party or parties
shall not relieve the party or parties from whom contribution may be sought from
any obligation it or they may have under this Section 6 or otherwise, except to
the extent that any

14

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party is materially prejudiced by the failure to give notice. No Person guilty
of fraudulent misrepresentation (within the meaning of Section 11(f) of the
Securities Act), shall be entitled to contribution from any Person who was not
guilty of such fraudulent misrepresentation.

        (f)    The indemnity and contribution agreements contained in this
Section 6 will be in addition to any liability which the indemnifying parties
may otherwise have to the indemnified parties referred to above. Each Purchaser
Indemnitee's obligations to contribute pursuant to this Section 6 are not joint
but are several in the proportion that the number of Shares sold by such
Purchaser Indemnitee bears to the number of Shares sold by all Purchaser
Indemnities.

7.    Additional Payments Under Certain Circumstances.

        (a)   Additional payments ("Additional Payments") with respect to the
Registrable Shares shall be assessed as follows if any of the following events
occur (each such event in clauses (i) through (iii) below being herein called a
"Registration Default"):

        (i)    the Mandatory Shelf Registration Statement has not been filed
with the Commission before January 1, 2005 or declared effective by the
Commission before July 1, 2005;

        (ii)   the Company fails, with respect to a Holder that supplies a
Notice and Questionnaire described in Section 2(a)(iii), to cause an amendment
to the already effective Mandatory Shelf Registration Statement to be filed or,
if permitted by the Commission, to prepare a Prospectus supplement to the
Mandatory Shelf Registration Statement and distribute such supplement to
Holders, in each case within the time period set forth in section 2(a)(iii) to
name such Holder as an additional selling securityholder; or

        (iii)  the Mandatory Shelf Registration Statement is declared effective
by the Commission but (A) the Mandatory Shelf Registration Statement thereafter
ceases to be effective during the period contemplated by Section 2(a)(i) or
(B) as specified in Section 5(a), the Mandatory Shelf Registration Statement or
the Prospectus ceases to be usable in connection with resales of Registrable
Shares during the periods specified herein and the Company fails to (1) cure the
Mandatory Shelf Registration Statement within five business days by a
post-effective amendment or a report filed pursuant to the Exchange Act or
(2) if applicable, terminate the suspension period described in Section 5(a) by
the 45/th or the 60/th/ day, as applicable.

        Each of the foregoing will constitute a Registration Default whatever
the reason for any such event and whether it is voluntary or involuntary or is
beyond the Company's control or pursuant to operation of law or as a result of
any action or inaction by the Commission.

        (b)   Additional Payments shall accrue on the Registrable Shares from
and including the date on which any such Registration Default occurs to but
excluding the date on which all such Registration Defaults have been cured,
(i) in the case of Preferred Shares at a rate of 0.5% per annum, and (ii) if the
Preferred Shares have been converted to Common Shares, $0.04 per Common Share
per annum (subject to adjustment for splits, recombinations and similar
matters); provided, however, that in no event shall Additional Payments accrue
under more than one of the foregoing clauses (a)(i)-(a)(iii) at any one time. In
the case of a Registration Default described in clause (a)(ii), the Company's
obligation to pay Additional Payments extends only to the affected Registrable
Shares. Other than the obligation of payment of any Additional Payments in
accordance with the terms hereof, the Company will have no other liabilities for
monetary damages with respect to its registration obligations. With respect to
each Holder, the Company's obligations to pay Additional Payments remain in
effect only so long as the securities held by the Holder are Registrable Shares.

        (c)   A Registration Default referred to in Section 5(a)(iii) shall be
deemed not to have occurred and be continuing, and no Additional Payments shall
accrue as a result thereof, in relation to the Mandatory Shelf Registration
Statement or the related prospectus if (i) (A) such Registration Default

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has occurred solely as a result of material events, with respect to the Company
that would need to be described in such Mandatory Shelf Registration Statement
or the related prospectus or (B) the Registration Default relates to any
information supplied or failed to be supplied by a Holder of Registrable
Securities and (ii) the Company is proceeding promptly and in good faith to
amend or supplement the Mandatory Shelf Registration Statement and related
prospectus to describe such events as required by Section 5; provided, however,
that in any case if such Registration Default occurs for a continuous period in
excess of 30 days beyond any permitted 45 or 60 day suspension period (as
provided by Section 5), Additional Payments shall be payable in accordance with
the above paragraph from the day such Registration Default occurs until such
Registration Default is cured.

        (d)   In the case of the Preferred Shares, any amounts of Additional
Payments due pursuant to Section 5(a) will be payable in cash on the regular
dividend payment dates described the certificate of designations for the
Preferred Shares. In the case of the Common Shares, any amounts of Additional
Payments pursuant to Section 5(a) will be payable in cash on the regular
dividend payment dates described in the certificate of designations with respect
to the Preferred Shares as if it were still in effect and related to the Common
Shares. The amount of Additional Payments will be determined on the basis of a
360-day year comprised of twelve 30-day months, and the actual number of days on
which Additional Payments accrued during such period.

8.    Termination of the Company's Obligations.

        The Company shall have no further obligations pursuant to this Agreement
at such time as no Registrable Shares are outstanding, provided, however, that
the Company's obligations under Sections 3, 6 and 10 of this Agreement shall
remain in full force and effect following such time.

9.    Limitations on Subsequent Registration Rights.

        From and after the date of this Agreement, the Company shall not,
without the prior written consent of the Holders of a majority of the then
outstanding Registrable Shares, enter into any agreement with any holder or
prospective holder of any securities of the Company that would allow such holder
or prospective holder to include such securities in the Mandatory Shelf
Registration Statement or Piggyback Registration Statement, if any, filed
pursuant to the terms hereof, unless under the terms of such agreement, such
holder or prospective holder may include such securities in any such
registration only to the extent that the inclusion of his securities will not
reduce the amount of Registrable Shares of the Holders that is included.

10.    Miscellaneous.

        (a)    Amendments and Waivers.    This Agreement may not be amended,
modified or supplemented, and waivers or consents to or departures from the
provisions hereof may not be given, without the written consent of the Company
and Holders beneficially owning a majority of the then outstanding Registrable
Shares; provided, however, that for purposes of this Agreement, Registrable
Shares owned, directly or indirectly, by an Affiliate of the Company shall not
be deemed to be outstanding. Notwithstanding the foregoing, a waiver or consent
to or departure from the provisions hereof with respect to a matter that relates
exclusively to the rights of a Holder whose securities are being sold pursuant
to a Registration Statement and that does not directly or indirectly affect,
impair, limit or compromise the rights of other Holders may be given by such
Holder; provided that the provisions of this sentence may not be amended,
modified or supplemented except in accordance with the provisions of the
immediately preceding sentence.

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        (b)    Notices.    All notices and other communications, provided for or
permitted hereunder shall be made in writing and delivered by facsimile (with
receipt confirmed), overnight courier or registered or certified mail, return
receipt requested, or by telegram, addressed as follows:

        (i)    if to a Holder, at the most current address given by the transfer
agent and registrar of the Shares to the Company;

        (ii)   if to the Company, at the offices of the Company at 1100
Louisiana Street, Suite 4400, Houston, Texas 77002, Attention: Stephen W. Herod,
(facsimile 832-204-2877); with copies (which shall not constitute notice) to:
(A) Hinkle Elkhouri Law Firm L.L.C., 2000 Epic Center, 301 North Main Street,
Wichita, Kansas 67202, Attention: David S. Elkouri, Esq. (Fax: (316) 264-1518)
and (B) Thompson & Knight LLP, 333 Clay Street, Suite 3300, Houston, Texas
77002, Attention: Dallas Parker, Esq. (facsimile 832-397-8110); and

        (iii)  if to FBR, at the offices of FBR at 1001 Nineteenth Street North,
Arlington, Virginia 22209, Attention: William Ginivan, Esq. (facsimile
(703) 312-9698); with a copy (which shall not constitute notice) to Akin Gump
Strauss Hauer & Feld LLP, 1111 Louisiana St., Houston, Texas 77002, Attention:
Julien R. Smythe, Esq. (facsimile (713) 236-0822).

        (c)    Successors and Assigns; Third Party Beneficiaries.    This
Agreement shall inure to the benefit of and be binding upon the successors and
assigns of each of the parties hereto and shall inure to the benefit of each
Holder. The Company agrees that the Holders shall be third party beneficiaries
to the agreements made hereunder by FBR and the Company, and each Holder shall
have the right to enforce such agreements directly to the extent it deems such
enforcement necessary or advisable to protect its rights hereunder; provided,
however, that such Holder fulfills all of its obligations hereunder.

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

        (e)    Governing Law.    THIS AGREEMENT SHALL BE GOVERNED BY AND
CONSTRUED IN ACCORDANCE WITH THE LAWS OF THE STATE OF NEW YORK, AS APPLIED TO
CONTRACTS MADE AND PERFORMED WITHIN THE STATE OF NEW YORK, WITHOUT REGARD TO
PRINCIPLES OF CONFLICTS OF LAW. EACH OF THE PARTIES HERETO HEREBY IRREVOCABLY
SUBMITS TO THE NONEXCLUSIVE JURISDICTION OF THE UNITED STATES DISTRICT COURT OF
THE SOUTHERN DISTRICT OF NEW YORK OR THE SUPREME COURT OF THE STATE OF NEW YORK
OR SITTING IN NEW YORK COUNTY IN RESPECT OF ANY SUIT, ACTION OR PROCEEDING
ARISING OUT OF OR RELATING TO THIS AGREEMENT, AND IRREVOCABLY ACCEPTS FOR ITSELF
AND IN RESPECT OF ITS PROPERTY, GENERALLY AND UNCONDITIONALLY, THE JURISDICTION
OF THE AFORESAID COURTS. EACH OF THE PARTIES HERETO IRREVOCABLY WAIVES, TO THE
FULLEST EXTENT IT MAY EFFECTIVELY DO SO UNDER APPLICABLE LAW, ANY OBJECTION THAT
IT MAY NOW OR HEREAFTER HAVE TO THE LAYING OF THE VENUE OF ANY SUCH SUIT, ACTION
OR PROCEEDING BROUGHT IN ANY SUCH COURT AND ANY CLAIM THAT ANY SUCH SUIT, ACTION
OR PROCEEDING BROUGHT IN ANY SUCH COURT HAS BEEN BROUGHT IN AN INCONVENIENT
FORUM.

        (f)    Severability.    If any term, provision, covenant or restriction
of this Agreement is held by a court of competent jurisdiction to be invalid,
illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their commercially reasonable efforts to find and employ an
alternative means to achieve the same or substantially the same result as that
contemplated by such term, provision, covenant or restriction. It is hereby
stipulated and declared to be the intention of the parties hereto that they
would have executed the remaining

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terms, provisions, covenants and restrictions without including any of such that
may be hereafter declared invalid, illegal, void or unenforceable.

        (g)    Entire Agreement.    This Agreement, together with the Placement
Agreement, is intended by the parties hereto as a final expression of their
agreement, and is intended to be a complete and exclusive statement of the
agreement and understanding of the parties hereto in respect of the subject
matter contained herein and therein.

        (h)    Registrable Shares Held by the Company or its
Affiliates.    Whenever the consent or approval of Holders of a specified
percentage of Registrable Shares is required hereunder, Registrable Shares held
by the Company or its Affiliates shall not be counted in determining whether
such consent or approval was given by the Holders of such required percentage.

        (i)    Survival.    This Agreement is intended to survive the
consummation of the transactions contemplated by the Placement Agreement. The
indemnification and contribution obligations under Section 6 of this Agreement
shall survive the termination of the Company's obligations under Section 2 of
this Agreement.

        (j)    Headings.    The headings in this Agreement are for convenience
of reference only and shall not limit or otherwise affect the provisions of this
Agreement. All references made in this Agreement to "Section" refer to such
Section of this Agreement, unless expressly stated otherwise.

[Remainder of this Page Intentionally Left Blank]

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        IN WITNESS WHEREOF, the parties have executed this Agreement as of the
date first above written.

    PETROHAWK ENERGY CORPORATION
 
 
By:
/s/  FLOYD C. WILSON      

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    Name: Floyd C. Wilson

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    Title: President and Chief Executive Officer

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FRIEDMAN, BILLINGS, RAMSEY & CO., INC.
(for the benefit of the Holders)
 
 
By:
/s/  JAMES R. KLEEBLATT      

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    Name: James R. Kleeblatt

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    Title: Senior Managing Director

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SCHEDULE A

INITIAL HOLDERS

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Exhibit 10.5

REGISTRATION RIGHTS AGREEMENT
SCHEDULE A INITIAL HOLDERS