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                                                                    EXHIBIT 4.46
                                                                  EXECUTION COPY


                           TRANSTEXAS GAS CORPORATION

                         Series A Junior Preferred Stock

                          REGISTRATION RIGHTS AGREEMENT


                                                                  March 15, 2000






                  TransTexas Gas Corporation, a Delaware corporation (the
"Company"), proposes, subject to the terms and conditions stated in the Second
Amended, Modified and Restated Plan of Reorganization dated January 25, 2000 and
pursuant to the Order dated February 7, 2000 of the United States Bankruptcy
Court for the Southern District of Texas (the "Plan"), to issue to the holders
of TransTexas Subordinated Notes, as defined in the Plan, named on the signature
page hereto (the "Initial Holders") certain shares of the Company's Series A
Junior Preferred Stock (the "Preferred Stock"). The Company hereby agrees as
follows:

                  1. Shelf Registration. The Company shall take the following
actions:

                  (a) The Company will at its cost, within seventy-five (75)
         days after the effective date of the Plan (the "Effective Date"), file
         with the Securities and Exchange Commission (the "Commission") and have
         declared effective as soon as practicable thereafter, a registration
         statement (the "Shelf Registration Statement") on an appropriate form
         under the Securities Act of 1933, as amended (the "Securities Act"),
         relating to the offer and sale of Transfer Restricted Stock (as defined
         in Section 7 below) by the Holders thereof from time to time in
         accordance with Rule 415 under the Securities Act; provided, however,
         that no Holder (other than the Initial Holders) shall be entitled to
         have the Preferred Stock held by it covered by such Shelf Registration
         Statement unless such Holder agrees in writing to be bound by all the
         provisions of this Agreement applicable to such Holder.

                  (b) The Company shall keep the Shelf Registration Statement
         continuously effective in order to permit the prospectus included
         therein to be lawfully delivered by the Holders of the relevant shares
         of the Preferred Stock until five years from the date hereof or for
         such shorter period that will terminate when all the Preferred Stock
         covered by the Shelf Registration Statement has been sold pursuant
         thereto.

                  (c) Notwithstanding any other provisions of this Agreement to
         the contrary, the Company shall cause the Shelf Registration Statement,
         and the related prospectus and any amendment or supplement thereto, as
         of the effective date of the Shelf Registration Statement, or amendment
         or supplement thereto, (i) to comply in all material respects with the
         applicable requirements of the Securities Act and the rules and
         regulations of the Commission and (ii) not to contain any untrue
         statement of a material fact or omit to state

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         a material fact required to be stated therein or necessary in order to
         make the statements therein, in light of the circumstances under which
         they were made, not misleading.

                  2. Registration Procedures. In connection with the
registration pursuant to Rule 415 under the Securities Act contemplated by
Section 1 hereof (the "Shelf Registration"), the following provisions shall
apply:

                  (a) At least three (3) days prior to the filing thereof with
         the Commission, the Company shall furnish to the Initial Holders a copy
         of the proposed form of the Shelf Registration Statement and each
         amendment thereto and each supplement, if any, to the prospectus
         included therein, and shall in its reasonable judgment reflect in each
         such document, when so filed with the Commission, such comments as such
         Initial Holders may reasonably propose.

                  (b) The Company shall give written notice to the Holders
         (which notice pursuant to clauses (ii) - (v) hereof shall be
         accompanied by an instruction to suspend the use of the prospectus
         until the requisite changes have been made):

                           (i) when the Shelf Registration Statement or any
                  amendment thereto has been filed with the Commission and when
                  the Shelf Registration Statement or any post-effective
                  amendment thereto has become effective;

                           (ii) of any request by the Commission for amendments
                  or supplements to the Shelf Registration Statement or the
                  prospectus included therein or for additional information;

                           (iii) of the issuance by the Commission of any stop
                  order suspending the effectiveness of the Shelf Registration
                  Statement or the initiation of any proceedings for that
                  purpose;

                           (iv) of the receipt by the Company or its legal
                  counsel of any notification with respect to the suspension of
                  the qualification of the Preferred Stock for sale in any
                  jurisdiction or the initiation or threatening of any
                  proceeding for such purpose; and

                           (v) of the happening of any event that requires the
                  Company to make changes in the Shelf Registration Statement or
                  the prospectus in order that the Shelf Registration Statement
                  or the prospectus does not contain an untrue statement of a
                  material fact nor omit to state a material fact required to be
                  stated therein or necessary to make the statements therein not
                  misleading.

                  (c) The Company shall make every reasonable effort to obtain
         the withdrawal at the earliest possible time of any order suspending
         the effectiveness of the Shelf Registration Statement.

                  (d) The Company shall furnish to each Holder included within
         the coverage of the Shelf Registration, without charge, at least one
         copy of the Shelf Registration Statement and any post-effective
         amendment thereto, including financial statements and

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         schedules, and, if the Holder so requests in writing, all exhibits
         thereto (including those, if any, incorporated by reference).

                  (e) The Company shall deliver to each Holder included within
         the coverage of the Shelf Registration, without charge, as many copies
         of the prospectus (including each preliminary prospectus) included in
         the Shelf Registration Statement and any amendment or supplement
         thereto as such person may reasonably request. The Company consents,
         subject to the provisions of this Agreement, to the use of the
         prospectus or any amendment or supplement thereto included in the Shelf
         Registration Statement by each of the selling Holders in connection
         with the offering and sale of the Preferred Stock covered by such
         prospectus or any such amendment or supplement.

                  (f) Prior to any public offering of the Preferred Stock
         pursuant to the Shelf Registration, the Company shall register or
         qualify or cooperate with the Holders of Preferred Stock included
         therein and their respective counsel in connection with the
         registration or qualification of the Preferred Stock for offer and sale
         under the securities or "blue sky" laws of such states of the United
         States as any Holder reasonably requests in writing and do any and all
         other acts or things necessary or advisable to enable the offer and
         sale in such jurisdictions of the Preferred Stock covered by the Shelf
         Registration Statement; provided, however, that the Company shall not
         be required to (i) qualify generally to do business in any jurisdiction
         where it is not then so qualified or (ii) take any action which would
         subject it to general service of process or to taxation in any
         jurisdiction where it is not then so subject.

                  (g) The Company shall cooperate with the Holders to facilitate
         the timely preparation and delivery of certificates representing the
         shares of Preferred Stock to be sold pursuant to the Shelf Registration
         Statement free of any restrictive legends and in such denominations and
         registered in such names as such Holders may request a reasonable
         period of time prior to sales of the Preferred Stock pursuant to the
         Shelf Registration Statement.

                  (h) Upon the occurrence of any event contemplated by
         paragraphs (ii) through (v) of Section 2(b) above during the period for
         which the Company is required to maintain an effective Shelf
         Registration Statement, the Company shall promptly prepare and file a
         post-effective amendment to the Shelf Registration Statement or a
         supplement to the related prospectus and any other required document so
         that, as thereafter delivered to Holders, the prospectus will not
         contain an untrue statement of a material fact or omit to state any
         material fact required to be stated therein or necessary to make the
         statements therein, in light of the circumstances under which they were
         made, not misleading. If the Company notifies the Holders in accordance
         with paragraphs (ii) through (v) of Section 2(b) above to suspend the
         use of the prospectus until the requisite changes to the prospectus
         have been made, then the Holders shall suspend use of such prospectus,
         and the period of effectiveness of the Shelf Registration Statement
         provided for in Section 1(b) above shall be extended by the number of
         days from and including the date of the giving of such notice to and
         including the date when the Holders shall have received such amended or
         supplemented prospectus pursuant to this Section 2(h).

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                  (i) The Company will comply with all rules and regulations of
         the Commission to the extent and so long as they are applicable to the
         Shelf Registration and will make generally available to its security
         holders (or otherwise provide in accordance with Section 11(a) of the
         Securities Act) an earnings statement satisfying the provisions of
         Section 11(a) of the Securities Act, no later than 45 days after the
         end of a 12-month period (or 90 days, if such period is a fiscal year)
         beginning with the first month of the Company's first fiscal quarter
         commencing after the effective date of the Shelf Registration
         Statement, which statement shall cover such 12-month period.

                  (j) The Company may require each Holder of shares of Preferred
         Stock to be sold pursuant to the Shelf Registration Statement to
         furnish to the Company such information regarding such Holder and the
         distribution of such shares as the Company may from time to time
         reasonably require for inclusion in the Shelf Registration Statement,
         and the Company may exclude from such Shelf Registration Statement the
         shares of Preferred Stock of any Holder that unreasonably fails to
         furnish such information within a reasonable time after receiving such
         request.

                  (k) The Company shall enter into such customary agreements
         (including, if requested, an underwriting agreement in customary form)
         and take all such other action, if any, as any Holder shall reasonably
         request in order to facilitate the disposition of shares of the
         Preferred Stock pursuant to the Shelf Registration in an underwritten
         offering or otherwise.

                  (l) The Company shall: (i) make reasonably available for
         inspection by the Holders, any underwriter participating in any
         disposition pursuant to the Shelf Registration Statement and any
         attorney, accountant or other agent retained by the Holders or any such
         underwriter, all relevant financial and other records, pertinent
         corporate documents and properties of the Company and (ii) cause the
         Company's officers, directors, employees, accountants and auditors to
         supply all relevant information reasonably requested by the Holders or
         any such underwriter, attorney, accountant or agent in connection with
         the Shelf Registration Statement, in each case as shall be reasonably
         necessary, in the judgment of such Holder or any such underwriter,
         attorney, accountant or agent referred to in this paragraph, to conduct
         a reasonable investigation within the meaning of Section 11 of the
         Securities Act; provided, however, that the foregoing inspection and
         information gathering shall be coordinated by the Initial Holders and
         on behalf of the other parties by counsel designated by and on behalf
         of such other parties as described in Section 3 hereof.

                  Until the Shelf Registration Statement is filed with the
         Commission, the Company may require each Holder to agree to keep
         confidential any non-public information, relating to the Company,
         received by such Holder in accordance with this Section 2(l) and not
         disclose such information (other than to an affiliate or prospective
         purchaser who agrees to respect the confidentiality provisions of this
         Section 2(l)); provided that each Holder shall be released from its
         confidentiality obligations hereunder to the extent necessary to permit
         such Holder to trade its Preferred Stock in compliance with the
         securities laws if the Company breaches its obligations to timely file
         the Shelf Registration Statement and each Holder shall be relieved of
         its confidentiality obligations


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         hereunder if the release of such information is required by law or
         necessary to respond to inquiries of regulatory authorities; provided,
         however, that no Holder shall be relieved of its confidentiality
         obligation with respect to any such information otherwise permitted to
         be released pursuant to this Section 2 (l) that is not material to the
         Company. The foregoing requirement shall exclude information which (i)
         is or becomes generally available to the public other than as a result
         of disclosure by the Holder or the Holder's Representatives, or (ii)
         becomes available to the Holder or any of the Holder's Representatives
         on a non-confidential basis from a source other than the Company or its
         affiliates or Representatives, provided that neither the Holder or any
         of the Holder's Representatives is aware that such source is under an
         obligation (whether contractual, legal or fiduciary) to the Company or
         its affiliates or Representatives to keep such information
         confidential. For purposes hereof, the "Representatives" of any entity
         means such entity's directors, officers, employees, legal and financial
         advisors, accounts and other agents and representatives.

                  (m) The Company, if requested by any Holder of shares of the
         Preferred Stock covered thereby, shall cause (i) its counsel to deliver
         an opinion and updates thereof relating to the Preferred Stock in
         customary form addressed to the selling Holders of the applicable
         Preferred Stock or the managing underwriters, if any, thereof and
         dated, in the case of the initial opinion, the effective date of such
         Shelf Registration Statement, it being agreed that the matters to be
         covered by such opinion shall include, without limitation, the due
         incorporation and good standing of the Company and its subsidiaries;
         the due authorization, execution and delivery of the relevant agreement
         of the type referred to in Section 3(k) hereof; the due authorization
         and issuance of the Preferred Stock; the absence of material legal or
         governmental proceedings involving the Company; the absence of
         governmental approvals required to be obtained in connection with the
         Shelf Registration Statement, the offering and sale of the Preferred
         Stock or any agreement of the type referred to in Section 3(k) hereof;
         the compliance as to form of such Shelf Registration Statement and any
         documents incorporated by reference therein and of the Indenture with
         the requirements of the Securities Act, respectively; and, as of the
         date of the opinion and as of the effective date of the Shelf
         Registration Statement or most recent post effective amendment thereto,
         as the case may be, the absence from such Shelf Registration Statement
         and the prospectus included therein, as then amended or supplemented,
         and from any documents incorporated by reference therein, of an untrue
         statement of a material fact or the omission to state therein a
         material fact required to be stated therein or necessary to make the
         statements therein not misleading (in the case of any such documents,
         in the light of the circumstances existing at the time that such
         documents were filed with the Commission under the Securities Exchange
         Act of 1934, as amended (the "Exchange Act"), all subject to customary
         assumptions and qualifications and otherwise in form and content
         customary for similar opinions; (ii) its officers to execute and
         deliver all customary documents and certificates and updates thereof
         requested by the selling Holders of the applicable shares of Preferred
         Stock or any underwriters of the applicable shares of Preferred Stock;
         and (iii) its independent public accountants to provide to the selling
         Holders of the applicable Preferred Stock and any underwriter therefor
         a comfort letter in customary form and covering matters of the type
         customarily covered in comfort letters in connection with primary
         underwritten offerings,


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         subject to receipt of appropriate documentation as contemplated, and
         only if permitted, by Statement of Auditing Standards No. 72.

                  (n) The Company and the Subsidiary Guarantors shall use their
         best efforts to take all other steps necessary to effect the
         registration of the Preferred Stock covered by the Shelf Registration
         Statement contemplated hereby.

                  3. Registration Expenses. The Company shall bear all fees and
expenses incurred in connection with the performance of its obligations under
Sections 1 and 2 hereof, whether or not the Shelf Registration is filed or
becomes effective, and, shall bear or reimburse the Holders of the Preferred
Stock covered thereby, for the reasonable fees and disbursements of one firm of
counsel designated by the Holders of a majority of the outstanding shares of the
Preferred Stock covered thereby to act as counsel for the Holders in connection
therewith.

                  4. Indemnification.

                  (a) The Company shall indemnify and hold harmless each Holder
         and each person, if any, who controls such Holder within the meaning of
         the Exchange Act (each such Holder and each such controlling person
         being referred to collectively as the "Indemnified Parties") from and
         against any losses, claims, damages or liabilities, joint or several,
         or any actions in respect thereof (including, but not limited to, any
         losses, claims, damages, liabilities or actions relating to purchases
         and sales of the Preferred Stock) to which each Indemnified Party may
         become subject under the Securities Act, the Exchange Act or otherwise,
         insofar as such losses, claims, damages, liabilities or actions arise
         out of or are based upon any untrue statement or alleged untrue
         statement of a material fact contained in the Shelf Registration
         Statement or any prospectus included therein or in any amendment or
         supplement thereto, or arise out of, or are based upon, the omission or
         alleged omission to state therein a material fact required to be stated
         therein or necessary to make the statements therein not misleading. The
         Company shall reimburse, as incurred, each Indemnified Party for any
         legal or other expenses reasonably incurred by it in connection with
         investigating or defending any such loss, claim, damage, liability or
         action in respect thereof. The Company shall not, however, be liable in
         any such case to the extent that such --------- ------- loss, claim,
         damage, liability or action arises out of or is based upon any untrue
         statement or alleged untrue statement or omission or alleged omission
         made in the Shelf Registration Statement or any prospectus included
         therein or in any amendment or supplement thereto or in any preliminary
         prospectus relating to the Shelf Registration in reliance upon and in
         conformity with written information pertaining to such Holder and
         furnished to the Company by or on behalf of such Holder specifically
         for inclusion therein. The Company shall also indemnify underwriters,
         selling brokers, dealer managers and similar securities industry
         professionals participating in the distribution (in each case as
         described in the Shelf Registration Statement), their officers and
         directors and each person who controls such persons within the meaning
         of the Securities Act or the Exchange Act to the same extent as
         provided above with respect to the indemnification of the Holders if
         requested by such Holders.

                  (b) Each Holder, severally and not jointly, will indemnify and
         hold harmless the Company and each person, if any, who controls the
         Company within the meaning of



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         the Securities Act or the Exchange Act from and against any losses,
         claims, damages, liabilities or actions in respect thereof to which the
         Company or any such controlling person may become subject under the
         Securities Act, the Exchange Act or otherwise, insofar as such losses,
         claims, damages, liabilities or actions arise out of or are based upon
         any untrue statement or alleged untrue statement of a material fact
         contained in the Shelf Registration Statement or any prospectus
         included therein or in any amendment or supplement thereto or in any
         preliminary prospectus relating to the Shelf Registration, or arise out
         of or are based upon the omission or alleged omission to state therein
         a material fact necessary to make the statements therein not
         misleading, but in each case only to the extent that the untrue
         statement or alleged untrue statement or omission or alleged omission
         was made in reliance upon and in conformity with written information
         pertaining to such Holder and furnished to the Company by or on behalf
         of such Holder specifically for inclusion therein; and, subject to the
         limitation set forth immediately preceding this clause, shall
         reimburse, as incurred, the Company for any legal or other expenses
         reasonably incurred by the Company or any controlling person in
         connection with investigating or defending any loss, claim, damage,
         liability or action in respect thereof. This indemnity agreement will
         be in addition to any liability which such Holder may otherwise have to
         the Company and any of their controlling persons.

                  (c) Promptly after receipt by an Indemnified Party under this
         Section 4 of notice of the commencement of any action or proceeding
         (including a governmental investigation), such Indemnified Party will,
         if a claim in respect thereof is to be made against any person (the
         "Indemnifying Party") under this Section 4, notify the Indemnifying
         Party of the commencement thereof; but the omission so to notify the
         Indemnifying Party will not, in any event, relieve the Indemnifying
         Party from any obligations to any Indemnified Party including the
         indemnification obligation provided in paragraph (a) or (b) above. In
         case any such action is brought against any Indemnified Party, and it
         notifies the Indemnifying Party of the commencement thereof, the
         Indemnifying Party will be entitled to participate therein and, to the
         extent that it may wish, jointly with any other Indemnifying Party
         similarly notified, to assume the defense thereof, with counsel
         reasonably satisfactory to such Indemnified Party (who shall not,
         except with the consent of the Indemnified Party, be counsel to the
         Indemnifying Party), and after notice from the Indemnifying Party to
         such Indemnified Party of its election to assume the defense thereof,
         the Indemnifying Party will not be liable to such Indemnified Party
         under this Section 4 for any legal or other expenses, other than
         reasonable costs of investigation, subsequently incurred by such
         Indemnified Party in connection with the defense thereof. No
         Indemnifying Party shall, without the prior written consent of the
         Indemnified Party, effect any settlement of any pending or threatened
         action 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 any claims that
         are the subject matter of such action.

                  (d) If the indemnification provided for in this Section 4 is
         unavailable or insufficient to hold harmless an Indemnified Party, then
         each Indemnified Party shall contribute to the amount paid or payable
         to such Indemnifying Party as a result of the losses, claims, damages
         or liabilities referred to in this Section 4 an amount or additional


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         amount, as the case may be, in such proportion as is appropriate to
         reflect the relative fault of the Indemnifying Party or parties on the
         one hand and the Indemnified Party on the other in connection with the
         statements or omission which resulted in such loses, claims, demands or
         liabilities as well as any other relevant equitable considerations. The
         relative fault 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 Indemnifying Party or parties on the one
         hand or the Indemnified Party on the other and the parties' relative
         intent, knowledge, access to information and opportunity to correct or
         prevent such untrue statement or omission. The amount paid to an
         Indemnified Party as a result of the losses, claims, damages or
         liabilities referred to in the first sentence of this Section 4 shall
         be deemed to include any legal or other expenses reasonably incurred by
         such Indemnified Party in connection with investigating or defending
         any action or claim which is the subject of this Section 4. 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.

                  (e) The agreements contained in this Section 4 shall survive
         the sale of the Preferred Stock pursuant to the Shelf Registration
         Statement and shall remain in full force and effect, regardless of any
         termination or cancellation of this Agreement or any investigation made
         by or on behalf of any indemnified party.

                  5. Rules 144 and 144A. The Company shall use commercially
reasonable efforts to file the reports required to be filed by it under the
Securities Act and the Exchange Act in a timely manner and, if at any time the
Company is not required to file such reports, it will, upon the request of any
Holder of Transfer Restricted Stock (as defined below), make publicly available
other information so long as necessary to permit sales of their Preferred Stock
pursuant to Rules 144 and 144A. The Company covenants that it will take such
further action as any Holder of Transfer Restricted Stock may reasonably
request, all to the extent required from time to time to enable such Holder to
sell Transfer Restricted Stock without registration under the Securities Act
within the limitation of the exemptions provided by Rules 144 and 144A
(including the requirements of Rule 144A (d) (4)). The Company will provide a
copy of this Agreement to prospective purchasers of Transfer Restricted Stock
identified to the Company upon request. Upon the request of any Holder of
Transfer Restricted Stock, the Company shall deliver to such Holder a written
statement as to whether the Company has complied with such requirements.

                  6. Underwritten Registrations. If any of the Transfer
Restricted Stock covered by the Shelf Registration is to be sold in an
underwritten offering, the managing underwriters will be selected by the Holders
of a majority in aggregate principal amount of such Transfer Restricted Stock to
be included in such offering.

                  No person may participate in any underwritten registration
hereunder unless such person (i) agrees to sell such person's Transfer
Restricted Stock on the basis reasonably provided in any underwriting
arrangements approved by the persons entitled hereunder to approve such
arrangements and (ii) completes and executes all questionnaires, powers of
attorney, indemnities,


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underwriting agreements and other documents reasonably required under the terms
of such underwriting arrangements.

                  7. Definitions:

                  "Holder" means the Initial Holders and any person or entity to
whom Transfer Restricted Stock is validly transferred by an Initial Holder or a
Holder pursuant to an exemption from the registration requirements of the
Securities Act other than Rule 144 promulgated under the Securities Act.

                  "Transfer Restricted Stock" means shares of Preferred Stock
issuable to the Initial Holders under the Plan, additional shares of Preferred
Stock payable as dividends thereon, if applicable, and common stock into which
the Preferred Stock is convertible until (i) the date on which such Preferred
Stock or common stock, as applicable, has been effectively registered under the
Securities Act and disposed of in accordance with the Shelf Registration
Statement or (ii) the date on which such Preferred Stock or common stock, as
applicable, is distributed to the public pursuant to Rule 144 under the
Securities Act.

                  8. Miscellaneous.

                  (a) Amendments and Waivers. The provisions of this Agreement
         may not be amended, modified or supplemented, and waivers or consents
         to departures from the provisions hereof may not be given, except by
         the Company and with the written consent of the Holders of 75% of then
         outstanding shares of the Preferred Stock affected by such amendment,
         modification, supplement, waiver or consent.

                  (b) Notices. All notices and other communications provided for
         or permitted hereunder shall be made in writing by hand delivery,
         first-class mail, facsimile transmission, or air courier which
         guarantees overnight delivery:

                  (1) if to a Holder, at the most current address given by such
         Holder to the Company in accordance with the provisions of this Section
         8(b), which address initially is, with respect to each Holder, the
         address of such Holder to which confirmation of the sale of such
         Preferred Stock to such Holder was first sent by the Company with
         copies in like manner to you as follows:

                                    Cadwalader, Wickersham & Taft
                                    100 Maiden Lane
                                    New York, New York 10038
                                    Fax No.:   (212) 504-6666
                                    Attention: Brian Hoffmann


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                  (2) if to the Company at the Company's address as follows:

                                    TransTexas Gas Corporation
                                    1300 North Sam Houston Parkway East
                                    Houston, Texas 77032-2949
                                    Fax No.:   (281) 986-8877
                                    Attention: Secretary

                  with a copy to:

                                    Gardere & Wynne, L.L.P.
                                    3000 Thanksgiving Tower
                                    1601 Elm Street, Suite 3000
                                    Dallas, TX  75201
                                    Fax No.:   (214) 999-3534
                                    Attention: C. Robert Butterfield

                  All such notices and communications shall be deemed to have
         been duly given: at the time delivered by hand, if personally
         delivered; three business days after being deposited in the mail,
         postage prepaid, if mailed; when receipt is acknowledged by recipient's
         facsimile machine operator, if sent by facsimile transmission; and on
         the day delivered, if sent by overnight air courier guaranteeing next
         day delivery.

                  (c) No Inconsistent Agreements. The Company has not, as of the
         date hereof, entered into, nor shall it, on or after the date hereof,
         enter into, any agreement with respect to its Preferred Stock that is
         inconsistent with the rights granted to the Holders herein or otherwise
         conflicts with the provisions hereof.

                  (d) Successors and Assigns. This Agreement shall be binding
         upon the Company and its respective successors and assigns; provided
         however, that no successor or assign may exercise any rights under this
         Agreement unless such successor or assign agrees in writing to be bound
         by the provisions hereof.

                  (e) Headings. The headings in this Agreement are for
         convenience of reference only and shall not limit or otherwise affect
         the meaning hereof.

                  (f) Governing Law. THIS AGREEMENT SHALL BE GOVERNED BY, AND
         CONSTRUED IN ACCORDANCE WITH, THE LAWS OF THE STATE OF NEW YORK WITHOUT
         REGARD TO PRINCIPLES OF CONFLICTS OF LAWS.

                  (g) Severability. If any one or more of the provisions
         contained herein, or the application thereof in any circumstance, is
         held invalid, illegal or unenforceable, the validity, legality and
         enforceability of any such provision in every other respect and of the
         remaining provisions contained herein shall not be affected or impaired
         thereby.


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                  If the foregoing is in accordance with your understanding of
our agreement, please sign and return to TransTexas a counterpart hereof,
whereupon this Agreement will become a binding agreement among the Company and
the Initial Holders in accordance with its terms.



                                       Very truly yours,



                                       TRANSTEXAS GAS CORPORATION



                                       By:
                                          -------------------------------------
                                           Name:
                                           Title:





[Junior Preferred Stock Registration Rights Agreement]

<PAGE>   12




                                    The foregoing Registration Rights Agreement
                                    is hereby confirmed and accepted as of the
                                    date first above written.

                                    Initial Holders

                                    CREDIT SUISSE FIRST BOSTON CORPORATION



                                    By:
                                       ----------------------------------------
                                        Name:
                                        Title

                                    OAKTREE CAPITAL MANAGEMENT, LLC
                                    as general partner and investment manager
                                    of certain funds and accounts it manages



                                    By:
                                       ----------------------------------------
                                        Name:
                                        Title



                                    By:
                                       ----------------------------------------
                                        Name:
                                        Title



[Junior Preferred Stock Registration Rights Agreement]