Document:

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                                                                   EXHIBIT 10.48

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                              AMENDED AND RESTATED

                          LIMITED PARTNERSHIP AGREEMENT

                                       OF

                          MOBILE SATELLITE VENTURES LP

                                November 12, 2004

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                                TABLE OF CONTENTS
                                                                            PAGE

ARTICLE I DEFINED TERMS.......................................................2

     Section 1.1      DEFINITIONS.............................................2

     Section 1.2      HEADINGS................................................8

     Section 1.3      INTERPRETATION..........................................8

ARTICLE II CONTINUATION AND TERM..............................................8

     Section 2.1      CONTINUATION............................................8

     Section 2.2      NAME....................................................9

     Section 2.3      TERM....................................................9

     Section 2.4      REGISTERED AGENT AND OFFICE.............................9

     Section 2.5      PRINCIPAL PLACE OF BUSINESS.............................9

     Section 2.6      QUALIFICATION IN OTHER JURISDICTIONS....................9

     Section 2.7      AGREEMENT...............................................9

ARTICLE III PURPOSE AND POWERS OF THE PARTNERSHIP.............................9

     Section 3.1      PURPOSE.................................................9

     Section 3.2      POWERS OF THE PARTNERSHIP..............................10

     Section 3.3      LIMITATIONS ON PARTNERSHIP POWERS......................10

ARTICLE IV CAPITAL CONTRIBUTIONS AND CAPITAL ACCOUNTS........................10

     Section 4.1      CAPITAL CONTRIBUTIONS..................................10

     Section 4.2      STATUS OF CAPITAL CONTRIBUTIONS........................10

     Section 4.3      LIMITED PARTNERSHIP INTEREST...........................11

     Section 4.4      CAPITAL ACCOUNTS.......................................11

ARTICLE V PARTNERS...........................................................11

     Section 5.1      POWERS OF LIMITED PARTNERS.............................11

     Section 5.2      NO GENERAL PARTNER LIABILITY...........................12

     Section 5.3      ACTIONS OF THE LIMITED PARTNERS........................12

     Section 5.4      PARTITION..............................................12

     Section 5.5      WITHDRAWAL.............................................12

     Section 5.6      REMOVAL OF THE GENERAL PARTNER BY LIMITED PARTNERS.....12

     Section 5.7      BANKRUPTCY, RESIGNATION, WITHDRAWAL, ETC. OF GENERAL
                      PARTNER................................................12

ARTICLE VI MANAGEMENT........................................................12

     Section 6.1      MANAGEMENT BY THE GENERAL PARTNER......................12

     Section 6.2      RESTRICTIONS...........................................13

     Section 6.3      GENERAL PARTNER'S TIME.................................13

     Section 6.4      NO LIABILITY; INDEMNITY................................13

     Section 6.5      RELIANCE BY THIRD PARTIES..............................14

     Section 6.6      GENERAL AUTHORITY......................................14

     Section 6.7      LIMITED LIABILITY......................................14

     Section 6.8      SPECIAL PURPOSE PROVISION..............................14

     Section 6.9      GRANT OF POWER OF ATTORNEY.............................14

     Section 6.10     TERMS OF GRANT.........................................15

     Section 6.11     SEPARATE FORM..........................................15

ARTICLE VII ALLOCATIONS......................................................15

     Section 7.1      PROFITS AND LOSSES.....................................15

     Section 7.2      SPECIAL ALLOCATIONS....................................16

     Section 7.3      ALLOCATION RULES.......................................17

     Section 7.4      SECTION 704(C) OF THE CODE.............................18

     Section 7.5      UNCERTAINTIES IN ALLOCATIONS AND DISTRIBUTIONS.........18

ARTICLE VIII DISTRIBUTIONS...................................................19

     Section 8.1      DISTRIBUTIONS..........................................19

     Section 8.2      DISTRIBUTIONS TO PAY TAXES.............................19

     Section 8.3      DISSOLUTION............................................19

     Section 8.4      WITHHOLDING TAXES......................................19

     Section 8.5      LIMITATIONS ON DISTRIBUTION............................20

     Section 8.6      CAPITAL PROCEEDS.......................................20

ARTICLE IX TRANSFERS; PARTNERSHIP REGISTRATION RIGHTS........................20

     Section 9.1      INCORPORATION OF SECTION 8 OF THE STOCKHOLDERS'
                      AGREEMENT..............................................20

     Section 9.2      PARTNERSHIP REGISTRATION RIGHTS........................20

ARTICLE X BOOKS AND RECORDS..................................................21

     Section 10.1     BOOKS, RECORDS AND FINANCIAL STATEMENTS................21

     Section 10.2     ACCOUNTING METHOD......................................22

     Section 10.3     AUDIT..................................................23

ARTICLE XI TAX MATTERS.......................................................23

     Section 11.1     TAX MATTERS PARTNER....................................23

     Section 11.2     ELECTION...............................................23

     Section 11.3     TAXATION AS PARTNERSHIP................................23

ARTICLE XII LIABILITY, EXCULPATION AND INDEMNIFICATION.......................24

     Section 12.1     LIABILITY..............................................24

     Section 12.2     EXCULPATION............................................24

     Section 12.3     INDEMNIFICATION........................................24

     Section 12.4     EXPENSES...............................................25

     Section 12.5     INSURANCE..............................................25

     Section 12.6     OUTSIDE BUSINESSES.....................................25

ARTICLE XIII DISSOLUTION, LIQUIDATION AND TERMINATION........................26

     Section 13.1     DISSOLUTION............................................26

     Section 13.2     NOTICE OF DISSOLUTION..................................26

     Section 13.3     LIQUIDATION............................................26

     Section 13.4     TERMINATION............................................27

     Section 13.5     CLAIMS OF THE LIMITED PARTNERS.........................27

ARTICLE XIV AMENDMENTS.......................................................27

     Section 14.1     AMENDMENTS.............................................27

ARTICLE XV MISCELLANEOUS.....................................................27

     Section 15.1     FURTHER ASSURANCES.....................................27

     Section 15.2     NOTICES................................................27

     Section 15.3     FAILURE TO PURSUE REMEDIES.............................28

     Section 15.4     CUMULATIVE REMEDIES....................................28

     Section 15.5     BINDING EFFECT.........................................28

     Section 15.6     SEVERABILITY...........................................29

     Section 15.7     COUNTERPARTS...........................................29

     Section 15.8     INTEGRATION............................................29

     Section 15.9     CONFIDENTIALITY........................................29

     Section 15.10    GOVERNING LAW; CONSENT TO JURISDICTION.................30

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                              AMENDED AND RESTATED

                          LIMITED PARTNERSHIP AGREEMENT

                                       OF

                          MOBILE SATELLITE VENTURES LP

                  THIS LIMITED PARTNERSHIP AGREEMENT OF MOBILE SATELLITE
VENTURES LP (the "PARTNERSHIP"), dated as of November 12, 2004, is entered into
by and among Mobile Satellite Ventures GP Inc., a Delaware corporation (the
"GENERAL PARTNER"), and each of the limited partners whose names are set forth
on the Schedule of Limited Partners attached as SCHEDULE I hereto (each
individually, a "LIMITED PARTNER," and collectively, together with any
Additional Limited Partners (as hereinafter defined) hereafter admitted to the
Partnership in accordance with this Agreement, the "LIMITED PARTNERS" and
together with the General Partner, the "PARTNERS.").

                  WHEREAS, Motient Corporation, a Delaware corporation, as sole
member, formed a limited liability company (the "LLC") pursuant to the Delaware
Limited Liability Company Act (6 Del. C. ss. 18-101, et seq., the "LLC ACT") by
filing a Certificate of Formation on June 16, 2000 with the SecretarY of State
of Delaware and entering into a limited liability company operating agreement
dated as of June 16, 2000; and

                  WHEREAS, the operating agreement of the LLC was amended and
restated effective as of June 29, 2000 by a certain First Amended and Restated
Limited Liability Company Agreement (the "LLC AGREEMENT"); and

                  WHEREAS, the members of the LLC and the General Partner
approved the conversion of the LLC to a Delaware limited partnership in
accordance with the terms and conditions set forth in the LLC Agreement and
pursuant to Section 18-216 of the LLC Act and Section 17-217 of the Delaware
Act, whereupon the members of the LLC and certain other Persons (as hereinafter
defined) became Limited Partners of the Partnership and Mobile Satellite
Ventures GP Inc. was admitted as general partner of the Partnership; and

                  WHEREAS, the General Partner, executed, delivered and filed
(or caused to be delivered and filed) the Certificate of Conversion and the
Certificate of Limited Partnership pursuant to the terms of Section 17-204 of
the Delaware Act on November 26, 2001; and

                  WHEREAS, certain of the parties hereto are parties to that
certain Limited Partnership Agreement of the Partnership, dated as of November
26, 2001, as amended on August 21, 2003 and April 2, 2004 (the "NOVEMBER 2001
PARTNERSHIP AGREEMENT"); and

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                  WHEREAS, the parties hereto wish to amend and restate the
November 2001 Partnership Agreement to, among other things, (i) provide that the
Partnership shall have one class of limited partnership interests; (ii)
eliminate all provisions relating to the class A preferred units of limited
partnership of the Partnership; and (iii) make certain other changes as provided
herein.

                  NOW, THEREFORE, in consideration of the agreements and
obligations set forth herein and for other good and valuable consideration, the
receipt and sufficiency of which are hereby acknowledged, the Partners hereby
agree as follows:

                                    ARTICLE I

                                  DEFINED TERMS

                  Section 1.1 DEFINITIONS. Unless the context otherwise
requires, the terms defined in this Article I shall, for the purposes of this
Agreement, have the meanings herein specified.

                  "ADDITIONAL LIMITED PARTNER" means a Person admitted to the
Partnership as a Limited Partner pursuant to Section 8.4 of the Stockholders'
Agreement.

                   "ADJUSTED CAPITAL ACCOUNT" means, with respect to any Limited
Partner, the balance in such Limited Partner's Capital Account, increased by
such Limited Partner's share of the Minimum Gain and "partner nonrecourse debt
minimum gain" (as defined in Treasury Regulations Section 1.704-2(i)(2)).

                  "ADJUSTED CAPITAL ACCOUNT DEFICIT" means, with respect to any
Limited Partner, the deficit balance, if any, in such Limited Partner's Capital
Account as of the end of the relevant Fiscal Year, after giving effect to the
following adjustments:

                  (i) Credit to such Capital Account any amounts which such
         Limited Partner is obligated to restore or is deemed to be obligated to
         restore pursuant to the penultimate sentences of Treasury Regulations
         ss.ss. 1.704-2(g)(1) and 1.704-2(i)(5); and

                  (ii) Debit to such Capital Account the items described in
         Treasury Regulations ss. 1.704-1(b)(2)(ii)(d)(4), (5) and (6).

The foregoing definition of Adjusted Capital Account Deficit is intended to
comply with the provisions of Treasury Regulations ss. 1.704-1(b)(2)(ii)(d) anD
shall be interpreted consistently therewith.

                  "AFFILIATE" means with respect to a specified Person, any
Person that directly or indirectly controls, is controlled by, or is under
common control with, the specified Person. As used in this definition, the term
"control" means the possession, directly or indirectly, of the power to direct
or cause the direction of the management and policies of a Person, whether
through ownership of voting securities, by contract or otherwise.

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                  "AGREEMENT" means this Amended and Restated Limited
Partnership Agreement of the Partnership, as amended, modified, supplemented or
restated from time to time.

                  "ANCILLARY AGREEMENTS" has the meaning set forth in the
Investment Agreement.

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

                  "CAPITAL ACCOUNT" means, with respect to any Limited Partner,
the account maintained for such Limited Partner in accordance with the
provisions of Section 4.4 hereof.

                  "CAPITAL CONTRIBUTION" means, with respect to any Limited
Partner, any contributions made to the Partnership pursuant to Section 4.1
hereof by such Limited Partner with respect to the Limited Partnership Interest
in the Partnership now or hereafter held or purchased by such Limited Partner.

                  "CAPITAL EVENT" means (a) a sale, transfer, or other
disposition of all or substantially all the assets of the Partnership or (b) any
dissolution and liquidation of the Partnership.

                  "CAPITAL PROCEEDS" means the proceeds received (or in the case
of a distribution of the Partnership in kind deemed received if the property
were sold for its Gross Asset Value) by the Partnership from a Capital Event but
excluding any amounts reasonably determined by the General Partner to be
necessary to provide a reasonable reserve for working-capital needs or any other
contingencies of the Partnership.

                   "CERTIFICATE OF CONVERSION" means the Certificate of
Conversion of the Partnership and any and all amendments thereto and
restatements thereof filed with the office of the Secretary of State of the
State of Delaware pursuant to the Delaware Act.

                  "CERTIFICATE OF LIMITED PARTNERSHIP" means the Certificate of
Limited Partnership of the Partnership and any and all amendments thereto and
restatements thereof filed on behalf of the Partnership with the office of the
Secretary of State of the State of Delaware pursuant to the Delaware Act.

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                   "CODE" means the Internal Revenue Code of 1986, as amended
from time to time, or any corresponding federal tax statute enacted after the
date of this Agreement. A reference to a specific section (ss.) of the Code
refers not only to such specific section but also to any corresponding provisioN
of any federal tax statute enacted after the date of this Agreement, as such
specific section or corresponding provision is in effect on the date of
application of the provisions of this Agreement containing such reference.

                   "COMPETING BUSINESSES" has the meaning set forth in Section
12.6 of this Agreement.

                  "CONFIDENTIAL INFORMATION" has the meaning set forth in
Section 15.9 of this Agreement.

                  "CONTROL PARTY" means (i) an Affiliate that has direct or
indirect majority voting control of a Limited Partner, or (ii) an Affiliate that
has a majority of its voting interests held, directly or indirectly, by a
Limited Partner or by Persons that have direct or indirect voting control of a
Limited Partner.

                   "COVERED PERSON" means any Limited Partner, any Affiliate of
a Limited Partner or any officers, directors, representatives, shareholders,
partners, employees, representatives or agents of a Limited Partner or their
respective Affiliates, or any directors, officers, shareholders, partners,
employees, representatives or agents of the Partnership or its Affiliates or any
liquidating trustee under Section 13.3.

                  "DELAWARE ACT" means the Delaware Revised Uniform Limited
Partnership Act, 6 Del. C. ss. 17-101, et seq., as amended from time to time.

                  "DEPRECIATION" means, for each Fiscal Year or other period, an
amount equal to the depreciation, amortization or other cost recovery deduction
allowable with respect to an asset for such Fiscal Year or other period;
provided, however, that if the Gross Asset Value of an asset differs from its
adjusted basis for federal income tax purposes at the beginning of such Fiscal
Year or other period, Depreciation shall be an amount that bears the same ratio
to such beginning Gross Asset Value as the federal income tax depreciation,
amortization or other cost recovery deduction with respect to such asset for
such Fiscal Year or other period bears to such beginning adjusted tax basis; and
provided further, that if the federal income tax depreciation, amortization or
other cost recovery deduction for such Fiscal Year or other period is zero,
Depreciation shall be determined with reference to such beginning Gross Asset
Value using any reasonable method selected by the General Partner.

                    "FISCAL YEAR" means (i) the period commencing upon the
formation of the Partnership and ending on December 31, 2001, (ii) any
subsequent twelve (12) month period commencing on January 1 and ending on
December 31, or (iii) any portion of the period described in clause (ii) of this
sentence for which the Partnership is required to allocate Profits, Losses and
other items of Partnership income, gain, loss or deduction pursuant to Article
VII hereof.

                  "GENERAL PARTNER" has the meaning set forth in the opening
paragraph of this Agreement.

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                   "GROSS ASSET VALUE" means, with respect to any asset, such
asset's adjusted basis for federal income tax purposes, except as follows:

                  (i) the initial Gross Asset Value of any asset contributed by
         a Limited Partner to the Partnership shall be the gross fair market
         value of such asset, as agreed to by the contributing Limited Partner
         and the General Partner;

                  (ii) the Gross Asset Value of all Partnership assets shall be
         adjusted to equal their respective gross fair market values, as
         determined in good faith by the General Partner, as of the following
         times: (a) the acquisition of an additional interest in the Partnership
         by any new or existing Limited Partner or any other adjustment in the
         Percentage Interests of the Limited Partners; (b) the distribution by
         the Partnership to a Limited Partner of more than a de minimis amount
         of Partnership assets as consideration for such Limited Partner's
         Limited Partnership Interest; and (c) the liquidation of the
         Partnership within the meaning of Treasury Regulations ss.
         1.704-1(b)(2)(ii)(g); and

                  (iii) the Gross Asset Value of any Partnership asset
         distributed to any Limited Partner shall be the gross fair market value
         of such asset on the date of distribution, as determined by the General
         Partner.

If the Gross Asset Value of an asset has been determined or adjusted pursuant to
clause (i) or (ii) above, such Gross Asset Value shall thereafter be adjusted by
the Depreciation taken into account with respect to such asset for purposes of
computing Profits and Losses.

                  "INITIAL PUBLIC OFFERING" means the closing of a firm
commitment underwritten public offering of equity interests in the Partnership
or its successor.

                   "INVESTORS" means each Limited Partner listed on SCHEDULE I
hereto as an Investor, each other Person admitted as an Investor after the date
hereof and, subject to Section 8.2(i) of the Stockholders' Agreement, any Person
acquiring all or part of the Limited Partnership Interest of an Investor that is
admitted as a Limited Partner as provided herein.

                  "INVESTMENT AGREEMENT" means that certain First Amended and
Restated Investment Agreement, dated as of August 8, 2003, among the MSV LP,
Motient Corporation, TMI Communications Delaware, Limited Partnership and the
investors named therein, as amended, restated, supplemented or revised from time
to time.

                  "LIMITED INVESTOR" means Dean Ventures VII, LLC and its
Affiliates that may own Limited Partnership Interests.

                  "LIMITED PARTNER" has the meaning set forth in the opening
paragraph of this Agreement.

                  "LIMITED PARTNERSHIP INTEREST" means a Limited Partner's
aggregate rights in the Partnership in accordance with this Agreement and the
Delaware Act, including such Limited Partner's right to share in the Profits and
Losses of the Partnership and right to receive distributions of the
Partnership's assets.

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                  "LLC" has the meaning set forth in the first "Whereas" clause.

                  "LLC ACT" has the meaning set forth in the first "Whereas"
clause.

                  "LLC AGREEMENT" has the meaning set forth in the second
"Whereas" clause.

                  "MINIMUM GAIN" has the meaning set forth in Treasury
                   Regulations ss.ss. 1.704-2(b)(2) and 1.704-2(d). "NOVEMBER
                   2001 PARTNERSHIP AGREEMENT" has the meaning set forth in the
                   fifth "Whereas" clause.

                   "PARTNER" has the meaning set forth in the opening paragraph
of this Agreement.

                  "PARENT TRANSFER/DRAG ALONG AGREEMENT" means that certain
Second Amended and Restated Parent Transfer/Drag Along Agreement, dated as of
the date hereof, by and among the Partnership and the parent entities and their
respective subsidiaries named therein.

                  "PARTNERSHIP" has the meaning set forth in the opening
paragraph of this Agreement.

                  "PERCENTAGE INTEREST" means with respect to any Limited
Partner, the ratio (expressed as a percentage) of the Units actually held by
such Limited Partner as of the date of determination to the aggregate Units
actually held by all Limited Partners on such date, and shall be reflected on
SCHEDULE I in accordance with Section 2.1(d). For purposes of voting and
providing consents under this Agreement and for purposes of Section 8 of the
Stockholders' Agreement, but not, for the avoidance of doubt, for purposes of
distributions of cash or tax and other economic rights under this Agreement,
"PERCENTAGE INTERESTS" means, with respect to each Limited Partner, the ratio
(expressed as a percentage) of the Units held by such Limited Partner as of the
date of determination to all Units held by all Limited Partners.

                  "PERSON" means any individual, corporation, association,
partnership (general or limited), joint venture, trust, estate, limited
liability company, or other legal entity or organization.

                  "PLEDGE AGREEMENT" means that certain Pledge and Guarantee
Agreement, dated as of November 26, 2001, by and among TMI Communications and
Company, Limited Partnership, TMI Communications Delaware, Limited Partnership
and the other parties thereto, as amended, supplemented or revised from time to
time.

                  "PROFITS" and "LOSSES" means, for each Fiscal Year an amount
equal to the Partnership's taxable income or loss for such Fiscal Year,
determined in accordance with ss. 703(a) of the Code (but including in taxable
income or loss, for this purpose, all items of income, gain, loss or deductioN
required to be stated separately pursuant to ss. 703(a)(1) of the Code), with
the following adjustments:

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                  (i) any income of the Partnership exempt from federal income
         tax and not otherwise taken into account in computing Profits or Losses
         pursuant to this definition shall be added to such taxable income or
         loss;

                  (ii) any expenditures of the Partnership described in ss.
         705(a)(2)(B) of the Code (or treated as expenditures described in ss.
         705(a)(2)(B) of the Code pursuant to Treasury Regulations ss.
         1.704-1(b)(2)(iv)(i)) and not otherwise taken into account in computing
         Profits or Losses pursuant tO this definition shall be subtracted from
         such taxable income or loss;

                  (iii) in the event the Gross Asset Value of any Partnership
         asset is adjusted in accordance with clause (ii) or (iii) of the
         definition of "Gross Asset Value" above, the amount of such adjustment
         shall be taken into account as gain or loss from the disposition of
         such asset for purposes of computing Profits or Losses;

                  (iv) gain or loss resulting from any disposition of any asset
         of the Partnership with respect to which gain or loss is recognized for
         federal income tax purposes shall be computed by reference to the Gross
         Asset Value of the asset disposed of, notwithstanding that the adjusted
         tax basis of such asset differs from its Gross Asset Value; and

                  (v) in lieu of the depreciation, amortization and other cost
         recovery deductions taken into account in computing such taxable income
         or loss, there shall be taken into account Depreciation for such Fiscal
         Year or other period, computed in accordance with the definition of
         "Depreciation" above.

Any items of income, gain, deduction and loss included within Profits and Losses
shall be determined in a manner consistent with Section 704(b) of the Code and
the Treasury Regulations thereunder.

                   "REQUIRED MAJORITY" means Limited Partners holding at least a
majority of the Percentage Interests held by the Limited Partners entitled to
vote on any matter as of the date of determination.

                  "REGULATORY ALLOCATIONS" has the meaning set forth in Section
7.2(f).

                   "STOCKHOLDERS' AGREEMENT" means the Stockholders' Agreement
by and among General Partner and the Limited Partners.

                  "TAX MATTERS PARTNER" has the meaning set forth in Section
11.1.

                   "TREASURY REGULATIONS" means the income tax regulations,
including temporary regulations, promulgated under the Code, as such regulations
may be amended from time to time (including corresponding provisions of
succeeding regulations).

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                  "UNIT" means a unit of interest in the partnership with the
rights and privileges specified herein for Units and representing a Percentage
Interest equal to one divided by the number Units then held by all Limited
Partners.

                  "VOTING AGREEMENT" means that certain Voting Agreement, dated
as of the date of this Agreement, by and among Spectrum Space IV Parallel, Inc.,
Spectrum Space Equity Investors IV, Inc., Spectrum Space IV Managers, Inc.,
Columbia Space (QP), Inc., Columbia Space (AI), Inc., Columbia Space Partners,
Inc., Telcom Satellite Ventures II, Inc., Telcom Satellite Ventures Inc., TMI
Communications Delaware, Limited Partnership, and MSV Investors, LLC.

                  Section 1.2 HEADINGS. The headings and subheadings in this
Agreement are included for convenience and identification only and are in no way
intended to describe, interpret, define or limit the scope, extent or intent of
this Agreement or any provision hereof.

                  Section 1.3 INTERPRETATION. Throughout this Agreement, nouns,
pronouns and verbs shall be construed as masculine, feminine, neuter, singular
or plural, whichever shall be applicable. All references herein to "Articles",
"Sections" and clauses shall refer to corresponding provisions of this
Agreement, unless otherwise specified.

                                   ARTICLE II

                              CONTINUATION AND TERM

                  Section 2.1 CONTINUATION.

         (a) The Partnership shall continue as a limited partnership under and
pursuant to the provisions of the Delaware Act and the Partners agree that the
rights, duties and liabilities of the Partners shall be as provided in the
Delaware Act, except as otherwise provided herein.

         (b) As of the date hereof, the Partnership shall have one class of
limited partnership interests and such class of interests shall be designated as
"Units."

         (c) Mobile Satellite Ventures GP Inc. shall act as the general partner
of the Partnership until such time as a Person is admitted as a successor to the
General Partner or as an additional general partner.

         (d) The name and mailing address of each Limited Partner, the number of
Units issued to such Limited Partner, the Percentage Interests represented
thereby, and the amount of each Limited Partner's Capital Account as of the date
of this Agreement is listed on SCHEDULE I attached hereto. The General Partner
shall update SCHEDULE I from time to time as necessary to reflect accurately the
information therein, including updates to reflect new issuances of Limited
Partnership Interests or assignments and transfers of all or any part of a
Limited Partner's Limited Partnership Interest, in each case, in accordance with
this Agreement and the Investment Agreement and indicating the name and address

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of such new Limited Partner, transferee or assignee along with an accurate
description of the Limited Partnership Interest so issued transferred or
assigned, including whether such new Limited Partner, transferee or assignee has
been or will be admitted to the Partnership as a substituted Limited Partner or
an Additional Limited Partner, as the case may be, and provide copies of the
same to the Partners. Any amendment or revision to SCHEDULE I made in accordance
with this Agreement and the Investment Agreement shall not be deemed an
amendment to this Agreement. Any reference in this Agreement to SCHEDULE I shall
be deemed to be a reference to SCHEDULE I as amended and in effect from time to
time.

                  Section 2.2 NAME. The name of the limited partnership formed
by this Agreement and by the filing of the Certificate of Conversion and the
Certificate of Limited Partnership is "Mobile Satellite Ventures LP." The
business of the Partnership may be conducted upon compliance with all applicable
laws under any other name designated, from time to time, by the General Partner.

                  Section 2.3 TERM. The term of the Partnership commenced on the
date of the filing of the certificate of formation of the LLC in the office of
the Secretary of State of the State of Delaware and shall continue until
dissolved in accordance with this Agreement, or if sooner, in accordance with
the Delaware Act.

                  Section 2.4 REGISTERED AGENT AND OFFICE. The Partnership's
registered agent and office in Delaware shall be CT Corporation System,
Wilmington, Delaware, 19801. At any time, the General Partner may designate
another registered agent and/or registered office, provided such new designation
shall not adversely affect any Partner.

                  Section 2.5 PRINCIPAL PLACE OF BUSINESS. The principal place
of business of the Partnership shall be at 10802 Parkridge Boulevard, Reston,
Virginia 20191. At any time, the General Partner may change the location of the
Partnership's principal place of business.

                  Section 2.6 QUALIFICATION IN OTHER JURISDICTIONS. The General
Partner shall cause the Partnership to be qualified, formed or registered under
assumed or fictitious name statutes or similar laws in any jurisdiction in which
the Partnership transacts business in which such qualification, formation or
registration is required or desirable.

                  Section 2.7 AGREEMENT. This Agreement completely amends,
restates and supersedes the November 2001 Partnership Agreement.

                                   ARTICLE III

                      PURPOSE AND POWERS OF THE PARTNERSHIP

                  Section 3.1 PURPOSE. The Partnership is formed for the object
and purpose of, and the nature of the business to be conducted and promoted by
the Partnership is, engaging in any lawful act or activity in which limited
partnerships may be engaged under the Delaware Act and engaging in any and all
activities necessary, convenient, desirable or incidental to the foregoing.

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                  Section 3.2 POWERS OF THE PARTNERSHIP. The Partnership shall
have the power and authority to take any and all actions necessary, appropriate,
proper, advisable, convenient or incidental to or for the furtherance of the
purposes set forth in Section 3.1.

                  Section 3.3 LIMITATIONS ON PARTNERSHIP POWERS. Notwithstanding
the foregoing provisions of Section 3.2, the Partnership shall not do business
in any jurisdiction that would jeopardize the limitation on liability afforded
to the Limited Partners under the Delaware Act or this Agreement in such
jurisdiction or elsewhere.

                                   ARTICLE IV

                   CAPITAL CONTRIBUTIONS AND CAPITAL ACCOUNTS

                  Section 4.1 CAPITAL CONTRIBUTIONS.

         (a) The General Partner shall not be required to make any Capital
Contribution to the capital of the Partnership, shall have no Capital Account
and shall not acquire a Percentage Interest or any Units, but shall nonetheless
be obligated to serve as the general partner of the Partnership pursuant to
Section 17-401(a) of the Delaware Act.

         (b) Capital Contributions shall be paid in the manner provided in the
Investment Agreement or a subscription agreement, as the case may be. Subject to
Section 8.1 of the Stockholders' Agreement, the Partnership may admit Persons as
Limited Partners and issue Units and Limited Partnership Interests to such
Persons without obligating such Persons to make Capital Contributions.

         (c) No Limited Partner shall be required or permitted to contribute
additional capital to the Partnership except that, subject to the pre-emptive
rights and other applicable provisions of Section 8 of the Stockholders'
Agreement incorporated herein, a Limited Partner shall be permitted to make
additional Capital Contributions pursuant to a subscription agreement approved
by the General Partner and the Required Majority.

                  Section 4.2 STATUS OF CAPITAL CONTRIBUTIONS.

         (a) Except as otherwise provided in this Agreement, no Limited Partner
shall demand or receive a return of its Capital Contribution and no return of a
Limited Partner's Capital Contribution shall be made hereunder if such
distribution would violate applicable state law. Under circumstances requiring a
return of any Capital Contribution, no Limited Partner shall have the right to
demand or receive property other than cash, except as may be specifically
provided in this Agreement.

         (b) No Limited Partner shall receive any interest, salary or drawing
with respect to its Capital Contribution or its Capital Account or for services
rendered on behalf of the Partnership or otherwise in its capacity as a Limited
Partner, except as otherwise specifically provided in this Agreement. Nothing
herein shall preclude any Limited Partner from serving the Partnership in
another capacity, including as an employee, contractor or consultant, or
otherwise dealing with the Partnership in its individual capacity and receiving
compensation or consideration therefor.

                                       10
<PAGE>

         (c) Except as otherwise provided herein or by applicable state law, the
Partners shall be liable only to make Capital Contributions as provided in
Section 4.1, and no Partner shall be required to lend any funds to the
Partnership nor to make any additional Capital Contributions. No Partner shall
have any personal liability for the repayment of any Capital Contribution of any
other Limited Partner.

                  Section 4.3 LIMITED PARTNERSHIP INTEREST. A Limited
Partnership Interest shall for all purposes be personal property. A Limited
Partner has no interest in specific Partnership property.

                  Section 4.4 CAPITAL ACCOUNTS.

         (a) An individual Capital Account shall be established and maintained
for each Limited Partner. Each Limited Partner's Capital Account as of the date
of this Agreement is reflected on SCHEDULE I hereto.

         (b) The Capital Account of each Limited Partner shall be maintained in
accordance with the following provisions:

                  (i) to such Limited Partner's Capital Account there shall be
         credited such Limited Partner's Capital Contribution, such Limited
         Partner's distributive share of Profits and items of gross income and
         gain and the amount of any Partnership liabilities that are assumed by
         such Limited Partner or that are secured by any Partnership assets
         distributed to such Limited Partner;

                  (ii) to such Limited Partner's Capital Account there shall be
         debited the amount of cash and the Gross Asset Value of any Partnership
         assets distributed to such Limited Partner pursuant to any provision of
         this Agreement, such Limited Partner's distributive share of Losses and
         items of gross deduction and loss and the amount of any liabilities of
         such Limited Partner that are assumed by the Partnership or that are
         secured by any property contributed by such Limited Partner to the
         Partnership; and

                  (iii) in determining the amount of any liability for purposes
         of this Subsection 4.4(b), there shall be taken into account ss. 752(c)
         of the Code and anY other applicable provisions of the Code and the
         Treasury Regulations.

                                    ARTICLE V

                                    PARTNERS

                  Section 5.1 POWERS OF LIMITED PARTNERS. Except as otherwise
specifically provided by this Agreement or required by the Delaware Act, no
Person other than the General Partner, including any Limited Partner acting in
its capacity as such, (a) shall have any right to "participate in the control of
the business" of the Partnership as such phrase is construed under Section
17-303(b) of the Delaware Act, (b) shall have the power to be an agent of the
Partnership or (c) shall take any action or exercise any right with respect to

                                       11
<PAGE>

the Partnership not permitted to be taken or exercised by a Limited Partner
pursuant to this Agreement and Section 17-303 of the Delaware Act. In no event
shall any Person, other than the General Partner, have any right, power or
authority (1) to transact any business in the name of the Partnership, (2) to
act for, or on behalf of, the Partnership or (3) to bind the Partnership, such
powers being vested solely and exclusively in the General Partner.

                  Section 5.2 NO GENERAL PARTNER LIABILITY. The General Partner
shall have no personal liability for the repayment of the Capital Contributions
of the Limited Partners.

                  Section 5.3 ACTIONS OF THE LIMITED PARTNERS. Any action of the
Partnership requiring the consent or approval of the Limited Partners, or any
percentage thereof, shall be taken by a consent in writing signed by Limited
Partners holding not less than the Percentage Interests necessary to take such
action pursuant to this Agreement.

                  Section 5.4 PARTITION. Each Limited Partner waives any and all
rights that it may have to maintain an action for partition of the Partnership's
property.

                  Section 5.5 WITHDRAWAL. A Limited Partner may not withdraw
from the Partnership prior to the dissolution and winding up of the Partnership
except as set forth in this Agreement or the Investment Agreement. A Limited
Partner attempting to resign in violation of this Agreement shall not be
entitled to receive any distribution and shall not otherwise be entitled to
receive the fair value of its Limited Partnership Interest except as otherwise
expressly provided for in this Agreement. The withdrawal of any Limited Partner
for any reason shall not result in the dissolution of the Partnership.

                  Section 5.6 REMOVAL OF THE GENERAL PARTNER BY LIMITED
PARTNERS. A Required Majority of the Limited Partners may at any time effect the
removal of the General Partner with or without cause by delivering to the
General Partner a notice of removal, such removal to become effective as
provided in such notice of removal.

                  Section 5.7 BANKRUPTCY, RESIGNATION, WITHDRAWAL, ETC. OF
GENERAL PARTNER. After the resignation, withdrawal, dissolution, Bankruptcy or
insolvency of the General Partner which would otherwise result in the
dissolution of the Partnership by operation of law, the Partnership will be
dissolved, unless, within ninety (90) days after the date of such resignation,
withdrawal, dissolution, Bankruptcy, or insolvency, the Required Majority agree
in writing to continue the business of the Partnership and to the appointment,
effective as of the date of withdrawal or removal, of one or more successor
General Partners.

                                   ARTICLE VI

                                   MANAGEMENT

                  Section 6.1 MANAGEMENT BY THE GENERAL PARTNER. Except as
otherwise expressly provided herein and subject to the restrictions contained in
Sections 5.1, 5.6. 5.7, 6.2 and 6.6 hereof, management of the Partnership and
control of its business shall be vested solely in the General Partner. Except
for situations in which the approval of the Limited Partners is required by this
Agreement, the Investment Agreement or by non-waivable provisions of applicable
law, the General Partner shall have the exclusive right, power and discretion to
manage, operate and control the Partnership, to do all things necessary or
appropriate to carry on its business and purposes, including but not limited to,
the right to incur and satisfy obligations relating to the formation and
operation of the Partnership, and to exercise all rights and powers conferred
upon the General Partner by the Delaware Act, in each case subject to the terms
and conditions set forth in this Agreement.

                                       12
<PAGE>

                  The General Partner shall have the power to delegate authority
to the officers and such other employees, agents and representatives of the
Partnership as it may from time to time deem appropriate and in accordance with
this Agreement. Any delegation of authority by the General Partner to take any
action must be approved by the General Partner in the same manner as would be
required for the General Partner to take such action directly.

                  Unless authorized to do so by this Agreement or by the General
Partner, no attorney-in-fact, employee, Limited Partner or other agent of the
Partnership shall have any power or authority to bind the Partnership in any
way, to pledge its credit or to render it liable monetarily for any purpose.

                  Section 6.2 RESTRICTIONS.

         (a) Notwithstanding the grant of authority to the General Partner under
Section 6.1 hereof, without the prior written consent of the Required Majority
of the disinterested Limited Partners, the General Partner shall not permit or
cause the Partnership to enter into transactions with its Limited Partners or
Affiliates of its Limited Partners except as otherwise permitted in the
Investment Agreement, this Agreement or the Ancillary Agreements.

         (b) Any vacancy in the position of General Partner shall be filled by
the affirmative written consent of the Required Majority.

                  Section 6.3 GENERAL PARTNER'S TIME. The General Partner shall
devote all of its time to the affairs of the Partnership.

                  Section 6.4 NO LIABILITY; INDEMNITY. Neither the General
Partner nor any of its officers, directors, employees or agents shall be liable,
responsible or accountable to the Partnership or any Partner for any act or
omission performed or omitted pursuant to the authority granted to it hereunder
or by law, or for any claim, loss, cost, damage, liability, demand or expense
(including, without limitation, attorneys' fees), resulting from the performance
of their duties hereunder in accordance with the requirements of this Agreement;
PROVIDED, HOWEVER, that any such Person shall be liable, accountable and
responsible for their willful misconduct. The Partnership shall indemnify the
General Partner, its officers, directors, employees and agents and hold them
harmless from any claim, loss, cost, damage, liability, demand or expense
(including, without limitation, attorneys' fees and disbursements), incurred or
sustained by them by reason of any act performed by them, or any omission by
them for or on behalf of the Partnership and in furtherance of its interest,
consistent with the requirements of this Agreement, but this indemnity shall not
require the Partners to make any Capital Contribution therefor; PROVIDED,
HOWEVER, such indemnity shall not extend to the willful misconduct of any such
Person.

                                       13
<PAGE>

                  Section 6.5 RELIANCE BY THIRD PARTIES. Third parties dealing
with the Partnership may rely conclusively upon the power and authority of the
General Partner to act as set forth herein and shall not be required to inquire
into or ascertain the authority of the General Partner so to act.

                  Section 6.6 GENERAL AUTHORITY. The General Partner shall,
except as otherwise provided in this Agreement, have all the rights and powers
and shall be subject to all the restrictions and liabilities of a general
partner in a limited partnership under the Delaware Act.

                  Section 6.7 LIMITED LIABILITY. Performance of one or more of
the acts described in Article V and this Article VI with respect to the Partners
shall not in any way impose any personal liability on any Limited Partner. No
Partner or, in the appropriate case, former Partner shall be liable for any
debts or obligations of the Partnership in excess of its Capital Contributions
(subject to the obligation of a Limited Partner of the Partnership under the
Delaware Act to repay any funds wrongfully distributed to it). All undistributed
cash, which would otherwise be distributed to the Limited Partners, shall be
available to creditors to satisfy the debts and obligations of the Partnership
prior to the time of actual distribution.

                  Section 6.8 SPECIAL PURPOSE PROVISION. The General Partner,
and any additional or substitute General Partner of the Partnership, may not be
an individual and shall at all times have as its sole purpose to act as the
General Partner of the Partnership, and shall be engaged in no other business or
have any other purpose. Any General Partner of the Partnership (a) shall have
organizational documents which conform in all material respects to the
organizational documents of the initial General Partner, and (b) shall be owned
by the Limited Partners pro rata in accordance with their Percentage Interests
from time to time, excluding for this purpose, any Limited Investor.

                  Section 6.9 GRANT OF POWER OF ATTORNEY. Each Limited Partner,
by its execution hereof, hereby irrevocably makes, constitutes and appoints the
General Partner as its true and lawful attorney-in-fact, with power and
authority in its name, place and stead, to make, execute, sign, acknowledge and
file on behalf of such Limited Partner and on behalf of the Partnership:

         (a) Such amendments to the Certificate of Limited Partnership as the
General Partner shall reasonably deem necessary or desirable consistent with
this Agreement;

         (b) All papers which may be deemed necessary or desirable by the
General Partner to effect the termination of the Partnership after its
dissolution as provided in this Agreement; and

         (c) All such other instruments, documents and certificates which may
from time to time be required or permitted by the laws of any state, the United
States of America, or any political subdivision or agency thereof, to
effectuate, implement, continue and defend the valid and subsisting existence,
rights and property of the Partnership as a limited partnership and its power to
carry out its purposes as set forth in this Agreement; PROVIDED, HOWEVER, that
any decisions other than administrative ones shall first have been approved by
the applicable approvals as provided herein.

                                       14
<PAGE>

         Section 6.10 TERMS OF GRANT. The foregoing appointment in Section 6.9:

         (a) Is irrevocable and shall be deemed to be a special power coupled
with an interest in recognition of the fact that the General Partner will be
relying upon such power of attorney to act as contemplated by this Agreement in
such execution, acknowledgment and filing and such other actions by the General
Partner on behalf of the Limited Partners and the Partnership;

         (b) Shall survive the dissolution or Bankruptcy of any Limited Partner
granting the same and the transfer, by operation of law or otherwise, by any
Limited Partner of the whole or any part of its interest in and to the
Partnership, its capital, Profits or Losses hereunder; and

         (c) May be exercised by the General Partner on behalf of any Limited
Partner by a facsimile signature of the General Partner, as attorney-in-fact for
such Limited Partner.

                  Section 6.11 SEPARATE FORM. The foregoing appointment is self
operative but, in confirmation thereof, each Limited Partner hereby agrees to
execute, acknowledge and deliver to the General Partner, promptly upon request
therefor by the General Partner, a power of attorney in recordable form
satisfactory to the General Partner evidencing the foregoing appointment.

                                   ARTICLE VII

                                   ALLOCATIONS

                  Section 7.1 PROFITS AND LOSSES.

         (a) Except as otherwise set forth in Section 7.1(b) or Section 7.2
hereof, Profits, Losses and items of income, gain, deduction and loss of the
Partnership for each Fiscal Year shall be allocated among all Persons who were
Limited Partners during such Fiscal Year in a manner that will, as nearly as
possible, cause the Adjusted Capital Account balance of each Limited Partner (as
computed for purposes of section 704(b) of the Code) at the end of such Fiscal
Year to be equal to the sum of the amounts of cash or the Gross Asset Value of
other property distributable to such Limited Partner pursuant to Article VIII
hereof at such time assuming that all the remaining assets of the Partnership
were sold for their Gross Asset Values, all debts of the Partnership were paid
according to their terms (with any nonrecourse debt for U.S. Federal income tax
purposes deemed paid in amounts not in excess of the Gross Asset Value of the
property securing such nonrecourse debt) and the cash or other property received
therefrom was distributed to the Limited Partners in accordance with the
priorities set forth in Article VIII hereof.

         (b) Notwithstanding Section 7.1(a), Losses allocated pursuant to
Section 7.1(a) to any Limited Partner for any Fiscal Year shall not exceed the
maximum amount of Losses that may be allocated to such Limited Partner without
causing such Limited Partner to have an Adjusted Capital Account Deficit at the
end of such Fiscal Year. Any Losses in excess of the limitation in this Section

                                       15
<PAGE>

7.1(b) shall be specially allocated solely to the other Limited Partners in
accordance with the priorities in Article VIII hereof to the maximum extent
permitted by this Section 7.1(b). In addition, Profits shall be allocated to
reverse any Losses specially allocated pursuant to the preceding sentence in
inverse order to those special loss allocations.

         (c) An allocation of Profits or Losses to a Limited Partner shall be
treated as an allocation to such Limited Partner of the same share of each item
of income, gain, loss and deduction that is taken into account in computing such
Profits or Losses, as the case may be.

                  Section 7.2 SPECIAL ALLOCATIONS. The following special
allocations shall be made in the following order:

         (a) MINIMUM GAIN CHARGEBACK. If there is a net decrease in Minimum Gain
(determined as provided in Treasury Regulations ss.ss. 1.704-2(d) and
1.704-2(G)) during any Fiscal Year, certain items of income and gain, including
gross income or gain, shall be allocated to the Limited Partners in the amounts
and manner described in Treasury Regulations ss. 1.704-2(f). This Section 7.2(a)
is intended to comply with the minimum gain chargeback requirement relating tO
partnership non-recourse liabilities (as defined in Treasury Regulations ss.
1.704-2(f)) and shall be so interpreted.

         (b) PARTNER NON-RECOURSE DEBT MINIMUM GAIN CHARGEBACK. If there is a
net decrease in Minimum Gain attributable to partner non-recourse debt
(determined pursuant to Treasury Regulations ss. 1.704-2(i)) during any Fiscal
Year, certain items of income and gain, including gross income or gain, shall be
allocateD as quickly as possible to those Limited Partners which had a share of
the Minimum Gain attributable to the partner non-recourse debt (such share
determined pursuant to Treasury Regulations ss. 1.704-1(i)(5)) in the amounts
and manner described in Treasury Regulations ss. 1.704-2(i) and (j). This
Section 7.2(b) is intended to comply with the minimum gain chargeback
requirement relating to partner non-recourse debt set forth in Treasury
Regulations ss. 1.704-2(i)(4)) anD shall be so interpreted.

         (c) ALLOCATION OF NON-RECOURSE DEDUCTIONS. Deductions attributable to
obligations with respect to which a Limited Partner bears the economic risk of
loss within the meaning of Treasury Regulation ss. 1.704-2(b)(4) shall be
allocated to the Limited Partner or Limited Partners that bear the economic risk
oF loss for such debt in accordance with the requirements of Treasury Regulation
ss. 1.704-2(i)(1). "Nonrecourse Deductions" (as such term is defined in TreasurY
Regulations ss.ss. 1.704-2(b)(1) and 1.704-2(c)) of the Partnership shall be
allocated to the Limited Partners in proportion to their Percentage Interests.

         (d) QUALIFIED INCOME OFFSET. In the event any Limited Partner
unexpectedly receives any adjustments, allocations or distributions described in
Treasury Regulations ss. 1.704-1(b)(2)(ii)(d)(4), (5) or (6), items of
Partnership income and gain (consisting of a pro rata portion of each item of
Partnership income, including gross income, and gain for such year) shall be
specially allocated to such Limited Partner in an amount and manner sufficient
to eliminate, to the extent required by the Treasury Regulations, the Adjusted

                                       16
<PAGE>

Capital Account Deficit of such Limited Partner as quickly as possible, provided
that an allocation pursuant to this Section 7.2(d) shall be made if and only to
the extent that such Limited Partner would have an Adjusted Capital Account
Deficit after all other allocations provided for in this Article VII have been
tentatively made as if this Section 7.2(d) were not in the Agreement.

         (e) GROSS INCOME ALLOCATION. In the event any Limited Partner has a
deficit Capital Account at the end of any Fiscal Year that is in excess of the
sum of (i) the amount such Limited Partner is obligated to restore and (ii) the
amount such Limited Partner is deemed to be obligated to restore pursuant to the
penultimate sentences of Treasury Regulations ss.ss. 1.704-2(g)(1) and
1.704-2(i)(5), such Limited Partner shall be specially allocated items of
PartnersHip income and gain (consisting of a pro rata portion of each item of
Partnership income, including gross income, and gain for such year) in the
amount of such excess as quickly as possible, provided that an allocation
pursuant to this Section 7.2(e) shall be made if and only to the extent that
such Limited Partner would have a deficit Capital Account in excess of such sum
after all other allocations provided for in this Article VII have been
tentatively made as if Section 7.2(d) above and this Section 7.2(e) were not in
the Agreement.

         (f) REGULATORY ALLOCATIONS. The allocations set forth in Section
7.2(a)-(e) hereof (the "REGULATORY ALLOCATIONS") are intended to comply with
certain requirements of the Treasury Regulations. It is the intent of the
Limited Partners that, to the extent possible, all Regulatory Allocations shall
be offset either with other Regulatory Allocations or with special allocations
of other items of Partnership income, gain, loss or deduction pursuant to this
Section 7.2(f). Therefore, the General Partner shall make such offsetting
special allocations of Partnership income, gain, loss and deduction in whatever
manner it determines appropriate, so that, after such offsetting allocations are
made, each Limited Partner's Capital Account balance is, to the extent possible,
equal to the Capital Account balance such Limited Partner would have if the
Regulatory Allocations were not part of the Agreement and all Partnership items
were allocated pursuant to Section 7.1. In exercising its discretion, the
General Partner shall take into account how future Regulatory Allocations
pursuant to Sections 7.2(a) and (b) hereof that, although not yet made, are
likely to offset other Regulatory Allocations previously made under Section
7.2(c) hereof.

         (g) SECTION 754 ADJUSTMENT. To the extent an adjustment to the adjusted
tax basis of any Partnership asset pursuant to ss. 734(b) or 743(b) of the CodE
is required, pursuant to Treasury Regulations ss. 1.704-1(b)(2)(iv)(m), to be
taken into account in determining Capital Accounts, the amount of such
adjustmenT to the Capital Accounts shall be treated as an item of gain (if the
adjustment increases the basis of the asset) or loss (if the adjustment
decreases such basis), and such gain or loss shall be specially allocated to the
Limited Partners in a manner consistent with the manner in which their Capital
Accounts are required to be adjusted pursuant to such regulation.

                  Section 7.3 ALLOCATION RULES.

         (a) For purposes of determining the Profits, Losses or any other items
allocable to any period, Profits, Losses and any such other items shall be
determined on a daily, monthly or other basis, as determined by the General
Partner using any method that is permissible under ss. 706 of the Code and thE
Treasury Regulations thereunder.

                                       17
<PAGE>

         (b) Except as otherwise provided in this Agreement, all items of
Partnership income, gain, loss, deduction and any other allocations not
otherwise provided for shall be divided among the Limited Partners in the same
proportions as they share Profits and Losses for the Fiscal Year in question.

         (c) The Limited Partners are aware of the income tax consequences of
the allocations made by this Article VII and hereby agree to be bound by the
provisions of this Article VII in reporting their shares of Partnership income
and loss for income tax purposes.

                  Section 7.4 SECTION 704(C) OF THE CODE.

         (a) In accordance with ss. 704(c) of the Code and the Treasury
Regulations thereunder, income, gain, loss and deduction with respect to any
propertY contributed to the capital of the Partnership shall, solely for income
tax purposes, be allocated among the Limited Partners so as to take account of
any variation between the adjusted basis of such property to the Partnership for
federal income tax purposes and its initial Gross Asset Value. The Limited
Partners acknowledge that the Gross Asset Values as of the date of this
Agreement shall be established by the General Partner in accordance with
Treasury Regulations ss. 1.704-1(b)(2)(iv)(f) to reflect the Capital Accounts as
shown on SCHEDULE I hereto.

         (b) In the event the Gross Asset Value of any Partnership asset is
adjusted pursuant to the definition of "Gross Asset Value" contained in Section
1.1 hereof, subsequent allocations of income, gain, loss and deduction with
respect to such asset shall take account of any variation between the adjusted
basis of such asset for federal income tax purposes and its Gross Asset Value in
the same manner as under ss. 704(c) of the Code and the Treasury RegulationS
thereunder.

         (c) Allocations pursuant to this Section 7.4 shall be calculated by the
General Partner using the traditional method under Code Section 704(c) and the
Treasury Regulations promulgated thereunder.

                  Section 7.5 UNCERTAINTIES IN ALLOCATIONS AND DISTRIBUTIONS. In
the event there is an ambiguity regarding the application of this Article VII or
Article VIII to a particular transaction, the income and expense from such
transaction shall be allocated among the Limited Partners, and distributions of
cash in respect of such transaction shall be made, in such proportions that the
General Partner, in its reasonable discretion, deems equitable, practicable and
consistent with this Agreement, the regulations under the Code and other
applicable law; PROVIDED, HOWEVER, that no such allocation or distribution by
the General Partner shall discriminate against any Limited Partner.

                                       18
<PAGE>

                                  ARTICLE VIII

                                  DISTRIBUTIONS

                  Section 8.1 DISTRIBUTIONS. Except as otherwise provided in
Section 8.2, Section 8.6 and Section 13.3 below, the Partnership shall make
distributions of cash to the Limited Partners in proportion to their respective
Percentage Interests at such time or times and in such amounts as the General
Partner may determine in its sole discretion.

                  Section 8.2 DISTRIBUTIONS TO PAY TAXES. Prior to March 15 of
the next following Fiscal Year, the General Partner shall distribute to the
Limited Partners an amount sufficient for the Limited Partners out of cash
available therefor to pay their tax liabilities which arise in respect of their
shares of cumulative net taxable income and gain of the Partnership for such
Fiscal Year, determined as set forth below by the General Partner, prior to the
making of any distributions pursuant to Sections 8.1 and 8.6 hereof. Any funds
distributed pursuant to this Section 8.2 shall reduce the amount that a Limited
Partner would otherwise receive pursuant to Sections 8.1 and 8.6. For purposes
of this Section 8.2, the amount of tax distributions made to a Limited Partner
for any Fiscal Year shall be equal to the excess, if any, of (i) the product of
(A) the excess, if any, of (I) its cumulative share of net taxable income or
gain for the current Fiscal Year and all prior Fiscal Years over (II) its
cumulative share of net taxable loss and deduction for all prior Fiscal Years
and (B) the sum of the highest rate of Canadian or United States federal, state,
provincial and local tax imposed on any Limited Partner calculated, with respect
to a Limited Partner that is a pass-through entity (for Canadian or United
States tax purposes), based on the type of taxpayer which the beneficial owners
of interests in such pass-through entity are for such year with respect to items
of the same character as such net income and gain, taking into account the
deductibility or creditability of federal, state, provincial and local taxes for
Canadian or United States federal income tax purposes and based on such
reasonable assumptions as the General Partner determines in good faith to be
appropriate (such assumptions not to include the effect of any net operating
losses or any other similar tax benefits available to a Limited Partner), over
(ii) the amount of any distributions made to such Limited Partner pursuant to
this Section 8.2 in a prior Fiscal Year.

                  Section 8.3 DISSOLUTION. Upon the dissolution and winding up
of the Partnership, the assets of the Partnership shall be distributed to the
Limited Partners as provided in Section 13.3 below.

                  Section 8.4 WITHHOLDING TAXES. All amounts withheld pursuant
to the Code or any provision of any state, local or foreign tax law with respect
to any payment, distribution or allocation to the Limited Partners shall be
treated as amounts distributed to the Limited Partners pursuant to this Article
VIII for all purposes of this Agreement. The Partnership is authorized to
withhold from distributions and to pay over to any federal, state, local or
foreign government any amounts required to be so withheld pursuant to the Code
or any provision of any other federal, state, local or foreign law and shall
allocate such amounts to those Limited Partners with respect to which such
amounts were withheld. Each Limited Partner shall indemnify the Partnership and
each of the Partners against any losses (including, without limitation, any tax
penalties and interest) incurred by reason of any failure by the Partnership to
make adequate deduction or withholding from any distribution made to such
Partner.

                                       19
<PAGE>

                  Section 8.5 LIMITATIONS ON DISTRIBUTION. Notwithstanding any
provision to the contrary contained in this Agreement, the Partnership shall not
make a distribution to the Limited Partners if such distribution in the
aggregate would violate Section 17-607 of the Delaware Act or other applicable
law.

                  Section 8.6 CAPITAL PROCEEDS. Following the receipt by the
Partnership of Capital Proceeds, a portion of such Capital Proceeds sufficient
for each Limited Partner to pay its tax liabilities which arise in respect of
the Capital Event giving rise to such Capital Proceeds, determined as set forth
in Section 8.2 above, shall be distributed to the Limited Partners pursuant to
Section 8.2 above. If the General Partner, in its sole discretion, determines
that the Partnership shall distribute any remaining Capital Proceeds, such
Capital Proceeds shall be distributed among the Limited Partners as follows:

         (a) First, to pay the creditors of the Partnership (including, for the
avoidance of doubt, any Limited Partners who may also be creditors of the
Partnership, but only to the extent of the indebtedness owed to such creditors);
and

         (b) Second, to the Limited Partners in a manner to cause the cumulative
prior and current Capital Proceeds distributed to each of the Limited Partners
to be in the same relative proportions as the Limited Partners' respective
Percentage Interests.

                                   ARTICLE IX

                   TRANSFERS; PARTNERSHIP REGISTRATION RIGHTS

                  Section 9.1 INCORPORATION OF SECTION 8 OF THE STOCKHOLDERS'
AGREEMENT. The provisions of Section 8 of the Stockholders' Agreement are hereby
incorporated by reference in their entirety in this Agreement. No Limited
Partner is a party to any other agreement, other than the Stockholders'
Agreement, the Investment Agreement, the Pledge Agreement, the Parent
Transfer/Drag Along Agreement and the Voting Agreement with respect to the
transfer or disposition of voting rights with respect to any Units.

                  Section 9.2 PARTNERSHIP REGISTRATION RIGHTS. Upon an Initial
Public Offering, the Partnership shall grant to each of the Limited Partners
customary registration rights in the securities of the Partnership commensurate
with such Limited Partner's Percentage Interest, PROVIDED, that such rights
shall not be exercisable in connection with the Initial Public Offering itself
and further provided that such registration rights shall be subject to the
provisions of any underwriting agreement entered into by the Partnership with
respect to such Initial Public Offering.

                                       20
<PAGE>

                                    ARTICLE X

                                BOOKS AND RECORDS

                  Section 10.1 BOOKS, RECORDS AND FINANCIAL STATEMENTS.

         (a) At all times during the continuance of the Partnership, the General
Partner shall maintain separate books of account for the Partnership that shall
show a true and accurate record of all costs and expenses incurred, all charges
made, all credits made and received and all income derived in connection with
the operation of the Partnership business, in accordance with generally accepted
accounting principles consistently applied to the extent not inconsistent with
this Agreement. Such books of account, together with a copy of this Agreement
and of the Certificate of Limited Partnership, shall at all times be maintained
at the principal place of business of the Partnership (or at the place of
business of the Person to whom the duty to maintain these books has been
delegated in accordance herewith and identified in writing to the Limited
Partners) and shall be open to inspection and examination at reasonable times by
each Limited Partner and its duly authorized representative for any purpose
reasonably related to such Limited Partner's interest as a Limited Partner of
the Partnership.

         (b) The General Partner shall prepare and maintain, or cause to be
prepared and maintained, the books of account of the Partnership. The following
financial information, which shall be certified to by an independent certified
public accountant, shall be transmitted by the General Partner to each Limited
Partner no later than three (3) months after the close of each Fiscal Year of
the Partnership:

                  (i) balance sheet of the Partnership as of the beginning and
         close of such Fiscal Year; and

                  (ii) statement of Partnership profits and losses for such
         Fiscal Year.

         (c) The General Partner shall also prepare and maintain, or cause to be
prepared and maintained, such records and information as shall be necessary to
assist the Limited Partners in preparing and filing tax returns and other
filings pertaining to tax matters. The following information shall be
transmitted by the General Partner to each Limited Partner no later than six (6)
months after the close of each Fiscal Year of the Partnership (except that, if
requested by a Limited Partner for purposes of such Limited Partner's tax
filing, the General Partner will use its reasonable best efforts to furnish such
information to such Limited Partner within four (4) months of the close of the
Fiscal Year of the Partnership):

                  (i) statement of such Limited Partner's Capital Account as of
         the close of such Fiscal Year, and changes therein during such Fiscal
         Year; and

                  (ii) statement indicating such Limited Partner's share of each
         item of Partnership income, gain, loss, deduction or credit for such
         Fiscal Year for income tax purposes.

                                       21
<PAGE>

         (d) For any Limited Partner that is (X) a company required to file
reports with the Securities and Exchange Commission (the "SEC") pursuant to
Sections 13 or 15(d) of the Securities Exchange Act of 1934, or a consolidated
subsidiary of such a company (such Limited Partner, a "PUBLIC LIMITED PARTNER")
and (Y) required by the SEC's rules and regulations as in effect from time to
time to file audited financial statements of the Partnership with the SEC, the
General Partner shall transmit the following financial information to such
Public Limited Partner, which information shall be certified to by an
independent certified public accountant, no later than fifteen (15) days before
the date on which such Public Limited Partner's annual report on Form 10-K (or
an equivalent report) is required to be filed by such Public Limited Partner
with the SEC:

                  (i) balance sheet of the Partnership as of the beginning and
         close of such Fiscal Year; and

                  (ii) statement of Partnership profits and losses for such
         Fiscal Year.

                  In addition, in any such case the General Partner will also
prepare, or cause to be prepared, audited financial statements of the
Partnership (including footnotes) meeting applicable requirements of the SEC's
rules and regulations with respect to financial statements to be included in
reports filed with the SEC, and will deliver such audited financial statements
to the Public Limited Partner no later than fifteen (15) days before the date
such Public Limited Partner is required to file the Partnership's audited
financial statements with the SEC.

         (e) Within three (3) months after the close of each Fiscal Year, the
General Partner shall send to each Limited Partner a Form K-1 tax statement or
any successor form thereto.

         (f) The General Partner shall prepare, or cause to be prepared, such
other statements as it deems necessary or advisable.

         (g) To the extent any Public Limited Partner is required to include
audited financial statements of the Partnership in such Public Limited Partner's
filings with the SEC, the General Partner will cooperate with such Public
Limited Partner and its accountants in resolving any questions regarding such
financial statements. In this regard, the General Partner will afford such
Public Limited Partner and its accountants reasonable access to the
Partnership's books and records, and will make the Partnership's officers and
employees available to such Public Limited Partner and its accountants during
normal business hours. The General Partner will also use its reasonable best
efforts to cause representatives of the Partnership's auditors to make
themselves available during normal business hours to address questions regarding
the Partnership's financial statements and/or the audit report thereon, by such
Public Limited Partner and/or its accountants.

                  Section 10.2 ACCOUNTING METHOD. For both financial and tax
reporting purposes and for purposes of determining profits and losses, the books
and records of the Partnership shall be kept on the accrual method of accounting
applied in a consistent manner and shall reflect all Partnership transactions
and be appropriate for the Partnership's business.

                                       22
<PAGE>

                  Section 10.3 AUDIT. The financial statements of the
Partnership shall be audited at the end of each Fiscal Year by an independent
certified public accountant selected by the General Partner, with such audit to
be accompanied by a report of such accountant containing its opinion. The cost
of such audits will be an expense of the Partnership. A copy of any such audited
financial statements and accountant's report will be made available for
inspection by the Limited Partners.

                                   ARTICLE XI

                                   TAX MATTERS

                  Section 11.1 TAX MATTERS PARTNER. The "TAX MATTERS PARTNER" of
the Partnership for purposes of ss. 6231(a)(7) of the Code shall be the General
Partner. The Tax Matters Partner and shall have the power to manage and control,
on behalf of the Partnership, any tax audit or administrative proceeding at the
Partnership level with the Internal Revenue Service relating to the
determination of any item of Partnership income, gain, loss, deduction or credit
for federal income tax purposes; PROVIDED, HOWEVER, that the Tax Matters Partner
shall not settle any tax audit or administrative proceeding without the consent
of a majority in interest of the affected Limited Partners. The Tax Matters
Partner shall be fully indemnified by the Partnership for all expenses incurred
by the Tax Matters Partner with respect to any such tax audit or administrative
proceeding. The Tax Matters Partner may be replaced by the holders of a Required
Majority of the Limited Partnership Interests.

                  Section 11.2 ELECTION. Upon the reasonable request of any
Limited Partner, the Tax Matters Partner shall make, or take all reasonable
efforts to revoke, an election on behalf of the Partnership, in accordance with
ss. 754 of the Code, so as to adjust the basis of Partnership property in the
case of A distribution of property within the meaning of ss. 734 of the Code,
and in the case of a transfer of a Partnership interest within the meaning of
ss. 743 of The Code. Each Limited Partner shall, upon request of the Tax Matters
Partner, supply the information necessary to give effect to such an election.

                  Section 11.3 TAXATION AS PARTNERSHIP. The Partners intend that
the Partnership will be treated as a partnership for U.S. federal income tax
purposes and, to the extent permitted under applicable law, all other income tax
purposes and the Partner will take such action, as is reasonably requested by
the General Partner, to make all elections and perform all acts as are necessary
to have the Partnership treated as such.

                                       23
<PAGE>

                                   ARTICLE XII

                   LIABILITY, EXCULPATION AND INDEMNIFICATION

                  Section 12.1 LIABILITY.

         (a) Except as otherwise provided by the Delaware Act, the debts,
obligations and liabilities of the Partnership, whether arising in contract,
tort or otherwise, shall be solely the debts, obligations and liabilities of the
Partnership, and no Covered Person shall be obligated personally for any such
debt, obligation or liability of the Partnership solely by reason of being a
Covered Person.

         (b) Except as otherwise expressly required by law, a Limited Partner,
in its capacity as Limited Partner, shall have no liability in excess of (a) the
amount of its Capital Contributions and its obligations hereunder to make
Capital Contributions, (b) its share of any assets and undistributed profits of
the Partnership, (c) its obligation to make other payments expressly provided
for in this Agreement, and (d) the amount of any distributions wrongfully
distributed to it as determined under the Delaware Act.

                  Section 12.2 EXCULPATION.

         (a) No Covered Person shall be liable to the Partnership or any other
Covered Person for any loss, damage or claim incurred by reason of any act or
omission performed, or omitted to be performed, by such Covered Person in good
faith on behalf of the Partnership and in a manner reasonably believed to be
within the scope of authority conferred on such Covered Person by this
Agreement, except that a Covered Person shall be liable for any such loss,
damage or claim incurred by reason of such Covered Person's willful misconduct,
fraud, gross negligence or breach of this Agreement.

         (b) A Covered Person shall be fully protected in relying in good faith
upon the records of the Partnership and upon such information, opinions, reports
or statements presented to the Partnership by any Person as to matters the
Covered Person reasonably believes are within such other Person's professional
or expert competence and who has been selected with reasonable care by or on
behalf of the Partnership, including information, opinions, reports or
statements as to the value and amount of the assets, liabilities, profits,
losses, or any other facts pertinent to the existence and amount of assets from
which distributions to Limited Partners might properly be paid.

                  Section 12.3 INDEMNIFICATION.

         (a) To the fullest extent permitted by applicable law, each Covered
Person shall be entitled to indemnification from the Partnership for any loss,
damage, claim or liability incurred by such Covered Person by reason of any act
or omission performed, or omitted to be performed, by such Covered Person in
good faith on behalf of the Partnership and within the scope of authority
conferred on such Covered Person by this Agreement, except that no Covered
Person shall be entitled to be indemnified in respect of any loss, damage, claim
or liability incurred by such Covered Person by reason of willful misconduct,
fraud, gross negligence or breach of this Agreement with respect to such acts or
omissions; provided, however, that any indemnity under this Section 12.3 shall
be provided out of and to the extent of Partnership assets only, and no Covered
Person shall have any personal liability on account thereof.

                                       24
<PAGE>

         (b) If any claim shall be asserted against a Covered Person, in respect
of which such Covered Person proposes to demand indemnification under this
Section 12.3 from the Partnership, such Covered Person shall notify the General
Partner to that effect with reasonable promptness after such assertion, and the
General Partner on behalf of the Partnership shall have the right to assume the
entire control of the defense or settlement of any such claim, through its own
attorneys and at its expense, and in connection therewith, such Covered Person
shall cooperate fully to make available to the Partnership and the General
Partner all information under its control relating thereto.

         (c) All rights to indemnification provided herein shall survive the
termination of this Agreement and the withdrawal, removal or insolvency of any
Partner; provided, that a claim for indemnification hereunder is made by or on
behalf of the Covered Person seeking such indemnification prior to the time
distribution in liquidation of the assets of the Partnership is made pursuant to
Article XIII.

         (d) The Partnership may enter into indemnity contracts with Covered
Persons and adopt written procedures pursuant to which arrangements are made for
the advancement of expenses and the funding of obligations under Section 12.4
and containing such other procedures regarding indemnification as are
appropriate.

                  Section 12.4 EXPENSES. To the fullest extent permitted by
applicable law, expenses (including legal fees) incurred by a Covered Person in
defending any claim, demand, action, suit or proceeding shall, from time to
time, be advanced by the Partnership prior to the final disposition of such
claim, demand, action, suit or proceeding upon receipt by the Partner of an
undertaking by or on behalf of the Covered Person to repay such amount if it
shall be determined that the Covered Person is not entitled to be indemnified as
authorized in Section 12.3 hereof.

                  Section 12.5 INSURANCE. The Partnership may purchase and
maintain insurance, to the extent and in such amounts as the General Partner
shall deem advisable, on behalf of Covered Persons and such other Persons as the
General Partner shall determine, against any liability that may be asserted
against or expenses that may be incurred by any such Person in connection with
the activities of the Partnership or such indemnities, regardless of whether the
Partnership would have the power to indemnify such Person against such liability
under the provisions of this Agreement.

                  Section 12.6 OUTSIDE BUSINESSES. The parties acknowledge that
Covered Persons have and may in the future have investments in other businesses
that may be similar to or competitive with the Partnership (collectively,
"COMPETING BUSINESSES") independent of their investments in the Partnership. By
virtue of its rights under this Section, no Covered Person shall have any
obligation to the Partnership to refrain from making investments in Competing
Businesses, or otherwise engaging in any commercial activity; and neither the
Partnership nor any other Covered Person shall have any right hereunder with

                                       25
<PAGE>

respect to any such investments or activities undertaken by such Covered Person.
Without limitation of the foregoing, this Agreement shall not be deemed to
restrict the rights of each Covered Person to engage in or possess an interest
in other business ventures of any nature or description, independently or with
others, similar or dissimilar to the business of the Partnership, and the
Partnership and the other Covered Persons shall have no rights or expectancy by
virtue of such Covered Person's relationships with the Partnership, this
Agreement or otherwise in and to such independent ventures or the income or
profits derived therefrom; and the pursuit of any such venture, even if such
investment is in a Competing Business, shall not be deemed wrongful or improper
hereunder. No Covered Person shall be obligated to present any particular
investment opportunity to the Partnership even if such opportunity is of a
character that, if presented to the Partnership, could be pursued by the
Partnership, and Covered Persons shall continue to have the right to take for
their own respective account or to recommend to others any such particular
investment opportunity. The provisions of this Section 12.6 shall in no way
limit or eliminate (i) Covered Persons' duties, responsibilities and obligations
with respect to any proprietary information of the Partnership, including any
applicable duty not to disclose or use such proprietary information improperly
or obtain therefrom an improper personal benefit, or (ii) Covered Persons'
obligations under the Investment Agreement or any agreement, instrument or
obligations (other than this Agreement).

                                  ARTICLE XIII

                    DISSOLUTION, LIQUIDATION AND TERMINATION

                  Section 13.1 DISSOLUTION. The Partnership shall be dissolved
and its affairs shall be wound up upon the first to occur of any of the
following:

         (a) consent of Limited Partners holding the Percentage Interests equal
to at least eighty percent (80%); or

         (b) the occurrence of any of the events set forth in Section 5.7 and
the failure of the Required Majority to agree to continue the Partnership as set
forth therein; or

         (c) the entry of a decree of judicial dissolution under Section 17-802
of the Delaware Act.

                  Section 13.2 NOTICE OF DISSOLUTION. Upon the dissolution of
the Partnership, the General Partner shall promptly notify the Limited Partners
of such dissolution.

                  Section 13.3 LIQUIDATION. Upon dissolution of the Partnership,
the General Partner or, if such dissolution has occurred in accordance with
Section 13.1(b), the Required Majority shall appoint a liquidating trustee who
shall immediately commence to wind up the Partnership's affairs; PROVIDED,
HOWEVER, that a reasonable time shall be allowed for the orderly liquidation of
the assets of the Partnership and the satisfaction of liabilities to creditors
so as to enable the Limited Partners to minimize the normal losses attendant
upon a liquidation. The Limited Partners shall continue to share Profits and
Losses during liquidation in the same proportions, as specified in Article VII
hereof, as before liquidation. The proceeds of liquidation shall be distributed,
as realized, in accordance with the provisions of Article VIII hereof.

                                       26
<PAGE>

                  Section 13.4 TERMINATION. The Partnership shall terminate when
all of the assets of the Partnership have been distributed in the manner
provided for in this Article XIII, and the Certificate of Limited Partnership
shall have been canceled in the manner required by the Delaware Act.

                  Section 13.5 CLAIMS OF THE LIMITED PARTNERS. The Limited
Partners and former Limited Partners shall look solely to the Partnership's
assets for the return of their Capital Contributions, and if the assets of the
Partnership remaining after payment of or due provision for all debts,
liabilities and obligations of the Partnership are insufficient to return such
Capital Contributions, the Limited Partners and former Limited Partners shall
have no recourse against the Partnership or any other Partner.

                                   ARTICLE XIV

                                   AMENDMENTS

                  Section 14.1 AMENDMENTS. Any amendments to this Agreement or
any waivers or consents hereunder, shall be adopted and be effective as an
amendment hereto or waiver or consent hereunder only if approved by the Required
Majority and, if such amendment, waiver or consent would adversely affect the
particular rights and interests of any Limited Partner disproportionately to the
adverse effects of such action on the rights and interests of other Limited
Partners, such action shall also require the consent of such Limited Partner;
PROVIDED, HOWEVER, that no provision of this Agreement which establishes a class
vote and/or minimum Percentage Interest required to take any action shall be
amended in any respect which would reduce such voting requirement, unless such
amendment is approved by such Limited Partners holding at least the Percentage
Interest that would have been required to take the action permitted to be taken
under the provision to be amended.

                                   ARTICLE XV

                                  MISCELLANEOUS

                  Section 15.1 FURTHER ASSURANCES. The Partners shall cooperate
with each other and the Partnership and shall promptly execute, acknowledge and
deliver any assurances, approvals or documents reasonably requested by a Limited
Partner that is necessary for the requesting Partner or the Partnership to
satisfy its obligations hereunder or obtain the benefits contemplated hereby.

                  Section 15.2 NOTICES. All notices provided for in this
Agreement shall be in writing, duly signed by the party giving such notice, and
shall be delivered personally, sent by a nationally recognized overnight
courier, telecopied or mailed by registered or certified mail, as follows:

                                       27
<PAGE>

         (a) If given to the Partnership, at the Partnership's mailing address
set forth below:

                           Mobile Satellite Ventures LP
                           10802 Parkridge Boulevard
                           Reston, Virginia  20191-5416
                           Fax:  (703) 390-2770
                           Attention:  General Counsel

         (b) If given to the General Partner, at the General Partner's mailing
address set forth below:

                             Mobile Satellite Ventures GP Inc.
                             10802 Parkridge Boulevard
                             Reston, Virginia  20191-5416
                             Fax:  (703) 390-2770
                             Attention:  General Counsel

         with a copy to each Limited Partner as set forth in clause (c) below.

         (c) If given to any Limited Partner, at the address set forth on
SCHEDULE I hereof (or as modified from time to time by a Limited Partner upon
written notice to the General Partner).

                  Notices delivered personally to an addressee or sent by
overnight courier shall be deemed to have been given upon such delivery. Notices
sent by telecopier shall be deemed to have been given upon confirmation by
telecopy answerback (provided that the sending of any such notice is followed
promptly by the mailing of the original of such notice). Notices mailed by
registered or certified mail shall be deemed to have been given upon the
expiration of five (5) days after such notice has been deposited in the mail.

                  Section 15.3 FAILURE TO PURSUE REMEDIES. The failure of any
party to seek redress for violation of, or to insist upon the strict performance
of, any provision of this Agreement shall not prevent a subsequent act, which
would have originally constituted a violation from having the effect of an
original violation. No waiver of any breach of any of the terms of this
Agreement shall be effective unless such waiver is in writing and signed by the
Partner against whom such waiver is claimed.

                  Section 15.4 CUMULATIVE REMEDIES. The rights and remedies
provided by this Agreement are cumulative and the use of any one right or remedy
by any party shall not preclude or waive its right to use any or all other
remedies. Said rights and remedies are given in addition to any other rights the
parties may have by law, statute, ordinance or otherwise.

                  Section 15.5 BINDING EFFECT. This Agreement shall be binding
upon and inure to the benefit of all of the parties and, to the extent permitted
by this Agreement, their successors, legal representatives and assigns.

                                       28
<PAGE>

                  Section 15.6 SEVERABILITY. The invalidity or unenforceability
of any particular provision of this Agreement shall not affect the other
provisions hereof, and this Agreement shall be construed in all respects as if
such invalid or unenforceable provision were omitted.

                  Section 15.7 COUNTERPARTS. This Agreement may be executed in
any number of counterparts with the same effect as if all parties hereto had
signed the same document. All counterparts shall be construed together and shall
constitute one instrument.

                  Section 15.8 INTEGRATION. This Agreement constitutes the
entire agreement among the parties hereto pertaining to the subject matter
hereof and thereof and supersedes all prior agreements and understandings
pertaining thereto.

                  Section 15.9 CONFIDENTIALITY. Each Partner acknowledges that
in the course of the formation, and during the operation, of the Partnership it
has or shall receive confidential and proprietary information concerning the
assets, business plans, intellectual property rights and operations of the
Partnership and the other Partners and Affiliates of such Persons ("CONFIDENTIAL
INFORMATION"). Each Partner agrees that the Confidential Information is a
valuable asset of the Partnership or its owner, as the case may be and its
public disclosure or use outside of the Partnership's activities without the
prior consent of the Partnership and/or the relevant Partner would cause
substantial harm to the Partnership, such disclosing Partner or other Person.
Therefore, each Partner agrees to treat all Confidential Information received by
it with the amount of care that a reasonable business person would use to
protect to its own valuable and proprietary confidential information and shall
not disclose any Confidential Information to any Person who does not have a
contractual obligation with the Partnership to keep such Confidential
Information confidential or does not have the right to have such Confidential
Information disclosed to it under an agreement with the Partnership. In
addition, each Partner shall not personally, and shall not permit other Persons
(including its Affiliates) to utilize Confidential Information for any purpose
other than for the benefit of the Partnership.

                  Notwithstanding the foregoing, a Partner may disclose
Confidential Information to its Affiliates, professional advisors, lenders and
investors if such Persons have agreed for the benefit of the Partnership, to
comply with the provision of this Section 15.9.

                  As used herein, "CONFIDENTIAL INFORMATION" shall not include
information (i) that has become generally available to the public through no
fault of the receiving Person, (ii) to the minimum extent necessary in order to
comply with any law, order, regulation, ruling or other governmental request
pursuant to subpoena or government order, provided that in the event a receiving
Person is subject to such a subpoena or order, it shall notify in writing the
General Partner of such event, and shall cooperate with any reasonable request
or efforts by the General Partner to take reasonable legally permissible actions
to limit the scope of disclosure required in order for such Person to comply
with such subpoena or order and (iii) as may be required or appropriate in
response to any report, statement or testimony submitted to any municipal, state
or national (including foreign regulatory bodies having or claiming to have
jurisdiction over such Person).

                                       29
<PAGE>

                  Section 15.10 GOVERNING LAW; CONSENT TO JURISDICTION This
Agreement and the rights of the parties hereunder shall be interpreted in
accordance with the laws of the State of Delaware, and all rights and remedies
shall be governed by such laws without regard to principles of conflict of laws.
Each party agrees that, in connection with any legal suit or proceeding arising
with respect to this Agreement, it shall submit to the non-exclusive
jurisdiction of the United States District Courts for the District of Delaware
and the Southern District of New York or the applicable Delaware or New York
state court and agrees to venue in such courts.

                                      * * *

                                       30
<PAGE>

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

                                     MOBILE SATELLITE VENTURES GP INC.

                                     By:      /S/ RANDY SEGAL
                                              ----------------------------------
                                              Name:    Randy Segal
                                              Title:   Secretary

                                     TMI COMMUNICATIONS DELAWARE, LIMITED
                                     PARTNERSHIP

                                     By: 3924505 CANADA INC.,
                                         Its General Partner

                                     By:      /S/ RORY MCCORMICK
                                              ----------------------------------
                                              Name:  Rory McCormick
                                              Title:  President

                                     TELCOM SATELLITE VENTURES II, INC.

                                     By:      /S/ HAL B. PERKINS
                                              ----------------------------------
                                              Name:  Hal B. Perkins
                                              Title: Vice President and General
                                                     Counsel

                                      TELCOM SATELLITE VENTURES, INC.

                                     By:      /S/ HAL B. PERKINS
                                              ----------------------------------
                                              Name:  Hal B. Perkins
                                              Title: Vice President and General
                                                     Counsel

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       31
<PAGE>

                                        SPECTRUM SPACE EQUITY INVESTORS IV, INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                                        SPECTRUM SPACE IV PARALLEL, INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                                        SPECTRUM SPACE IV MANAGERS, INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                                        SPECTRUM SPACE EQUITY INVESTORS IV-II,
                                        INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       32
<PAGE>

                                        SPECTRUM SPACE IV PARALLEL II, INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                                        SPECTRUM SPACE IV MANAGERS II, INC.

                                        By:      /S/ KEVIN J. MARONI
                                                 -------------------------------
                                                 Name:  Kevin J. Maroni
                                                 Title:  Authorized Signatory

                                        COLUMBIA SPACE (QP) II, INC.

                                        By:      /S/ DONALD A. DOERING
                                                 -------------------------------
                                                 Name:  Donald A. Doering
                                                 Title:  Authorized Signatory

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       33
<PAGE>

                                          COLUMBIA SPACE (AI) II, INC.

                                          By:      /S/ DONALD A. DOERING
                                                   -----------------------------
                                                   Name:  Donald A. Doering
                                                   Title:  Authorized Signatory

                                          COLUMBIA SPACE PARTNERS II, INC.

                                          By:      /S/ DONALD A. DOERING
                                                   -----------------------------
                                                   Name:  Donald A. Doering
                                                   Title:  Authorized Signatory

                                          COLUMBIA SPACE (QP), INC.

                                          By:      /S/ DONALD A. DOERING
                                                   -----------------------------
                                                   Name:  Donald A. Doering
                                                   Title:  Authorized Signatory

                                          COLUMBIA SPACE (AI), INC.

                                          By:      /S/ DONALD A. DOERING
                                                   -----------------------------
                                                   Name:  Donald A. Doering
                                                   Title:  Authorized Signatory

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       34
<PAGE>

                                        COLUMBIA SPACE PARTNERS, INC.

                                        By:      /S/ DONALD A. DOERING
                                                 -------------------------------
                                                 Name:  Donald A. Doering
                                                 Title:  Authorized Signatory

                                        MOTIENT VENTURES HOLDING INC.

                                        By:      /S/ CHRIS DOWNIE
                                                 -------------------------------
                                                 Name:  Chris Downie
                                                 Title:  EVP & COO

                                        MSV INVESTORS, LLC

                                        By:      /S/ JEFFREY A. LEDDY
                                                 -------------------------------
                                                 Name:  Jeffrey A. Leddy
                                                 Title:  CEO

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       35
<PAGE>

BY EXECUTING THIS AGREEMENT, DEAN VENTURES VII, LLC HEREBY ACCEPTS THE
OBLIGATIONS OF A LIMITED PARTNER AND ACKNOWLEDGES THAT ITS RIGHTS AS A LIMITED
PARTNER ARE LIMITED AS SET FORTH IN SECTION 5 OF THE SUBSCRIPTION AGREEMENT
DATED NOVEMBER 2, 2001 BETWEEN MOBILE SATELLITE VENTURES LLC AND DEAN VENTURES
VII, LLC AND SECTION 5 THEREOF IS HEREBY INCORPORATED BY REFERENCE INTO THIS
AGREEMENT WITH RESPECT TO DEAN VENTURES VII, LLC, ITS SUCCESSORS AND ASSIGNS:

                                          DEAN VENTURES VII, LLC

                                          By:      /S/ DEAN L. WILDE, JR.
                                                   -----------------------------
                                                   Name:  Dean L. Wilde, Jr.
                                                   Title:  Member

                 [SIGNATURE PAGE TO A & R PARTNERSHIP AGREEMENT]

                                       36<PAGE>

                                                                   EXHIBIT 10.49

                  AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT

                  AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT (this
"AGREEMENT"), dated as of November 12, 2004, by and among Mobile Satellite
Ventures GP Inc., a Delaware corporation ("GENERAL PARTNER") and General Partner
of Mobile Satellite Ventures LP, a Delaware limited partnership ("MSV LP") and
the stockholders of General Partner listed on SCHEDULE I hereto (each
individually, a "STOCKHOLDER," and collectively, the "STOCKHOLDERS").

                                    RECITALS

                  WHEREAS, each Stockholder is also a limited partner of MSV LP
and owns a portion of the common stock, par value $0.01 per share (the "Stock"),
of General Partner in proportionate amounts based upon its respective ownership
interests in MSV LP; and

                  WHEREAS, the Stockholders formed General Partner for the
purpose of having it serve exclusively as General Partner of MSV LP pursuant to
the terms of the MSV LP Agreement (as defined herein); and

                  WHEREAS, the Stockholders wish to assure that General Partner
performs its duties under the MSV LP Agreement and the other agreements by and
among the Stockholders strictly in accordance with the terms of this Agreement;
and

                  WHEREAS, MSV LP and General Partner have entered into a
purchase agreement (the "PURCHASE AGREEMENT") with Motient Ventures Holding Inc.
("MOTIENT SUB"), pursuant to which such investor will make an equity investment
in MSV LP and General Partner; and

                  WHEREAS, certain of the parties hereto are parties to that
certain Stockholders' Agreement, dated as of November 26, 2001, as amended (the
"NOVEMBER 2001 STOCKHOLDERS' AGREEMENT"); and

                  WHEREAS, in connection with the transactions contemplated by
the Purchase Agreement, the parties hereto wish to amend and restate the
November 2001 Stockholders' Agreement as provided herein.

                  NOW, THEREFORE, in consideration of the agreements contained
herein and for other good and valuable consideration, the receipt and
sufficiency of which is hereby acknowledged, the parties hereby agree as
follows:

                  Section 1. DEFINITIONS. Initially capitalized terms used, but
not defined herein, shall have the meanings ascribed thereto in the MSV LP
Agreement or, if not defined therein, in the Investment Agreement, as
applicable. Additionally, terms defined in this Section 1 shall, for the
purposes of this Agreement, have the meanings herein specified.

<PAGE>

                  "BUSINESS DAY" means a day of the year on which banks are not
required or authorized to close in New York City.

                  "COLUMBIA INVESTOR GROUP" means the entities in Columbia Space
(QP), Inc.'s investor group as set forth in SCHEDULE I hereto.

                  "CONTROL PARTY" means (i) an Affiliate that has direct or
indirect majority voting control of a Limited Partner, or (ii) an Affiliate that
has a majority of its voting interests held, directly or indirectly, by a
Limited Partner or by Persons that have direct or indirect voting control of a
Limited Partner.

                  "EXCLUDED SECURITIES" means (i) any interests in MSV LP issued
pursuant to the October 2001 Investment Agreement or any of the transactions
contemplated thereby, (ii) any interests in MSV LP issued pursuant to the
Investment Agreement or any of the transactions contemplated thereby, (iii) any
interests in MSV LP issued in connection with the acquisition of the business of
another entity, whether by the purchase of equity securities, assets or
otherwise, (iv) any interests in MSV LP issued as part of an Initial Public
Offering or other registered underwritten public offering of MSV LP's
securities, (v) any interests in MSV LP issued under an employee compensation
plan approved by the General Partner, (vi) any interests in MSV LP issued to
financial institutions, financial syndicates or lessors in connection with bona
fide commercial credit arrangements, equipment financings, or similar
transactions for primarily other than equity financing purposes, (vii) any
interests in MSV LP issued pursuant to Section 8.1(h)(vi) of this Agreement and
(viii) 4,817 Units that may be issued to inOvate Communications Group Services
Company or its Affiliates.

                  "FAMILY MEMBER" means, with respect to any Person (i) the
spouse, parents, children, siblings, mother and father-in-law, sons and
daughters-in-law and brothers and sisters-in-law of such Person or of any of the
beneficial owners of such Person, (ii) any trust whose beneficiaries consist of
only one or more of such Person and such persons or (iii) any partnership or
other entity whose owners are one or more of such Person and such persons.

                  "INVESTMENT AGREEMENT" means that certain First Amended and
Restated Investment Agreement, dated as of August 8, 2003, as amended, by and
among the Stockholders (and their affiliates) and certain other parties.

                  "INVESTOR" has the meaning set forth in the MSV LP Agreement.

                  "INVESTOR GROUP" means, with respect to Investors in the
Telcom Investor Group, the Columbia Investor Group and the Spectrum Investor
Group, such Investor's Investor Group as identified on SCHEDULE I hereto.

                                       2
<PAGE>

                  "INTERVENING ENTITY" means, as applied to any Limited Partner
at any time, any Person the value of which at such time consists principally of
its direct or indirect ownership of interests in, or obligations of, MSV LP or
Canadian Holdco. Without limiting the foregoing, the parties stipulate that, as
of the date hereof, TMI and TMI's general partner are Intervening Entities.

                  "MSV LP AGREEMENT" means that certain Amended and Restated
Limited Partnership Agreement of MSV LP, dated as of November 12, 2004, by and
among General Partner and the limited partners named therein.

                  "OCTOBER 2001 INVESTMENT AGREEMENT" means that certain Amended
and Restated Investment Agreement, dated as of October 12, 2001, as amended, by
and among the Stockholders (and their affiliates) and certain other parties.

                  "PLEDGE AGREEMENT" means that certain Pledge and Guarantee
Agreement, dated as of November 26, 2001, by and among TMI, TMI Sub and the
other parties thereto, as amended, supplemented or revised from time to time.

                  "REQUIRED MAJORITY" means Limited Partners holding at least a
majority of the Percentage Interests held by the Limited Partners entitled to
vote on any matter as of the date of determination.

                  "SPECTRUM INVESTOR GROUP" means the entities in Spectrum Space
Equity Investors IV, Inc.'s investor group as set forth in SCHEDULE I hereto.

                  "TELCOM INVESTOR GROUP" means the entities in Telcom Satellite
Ventures Inc.'s investor group as set forth in SCHEDULE I hereto.

                  "TMI SUB" means TMI Communications Delaware, Limited
Partnership.

                  "VOTING AGREEMENT" has the meaning set forth in Section 11(a).

Section 2.        BOARD COMPOSITION.

                  (a) QUALIFICATIONS OF DIRECTORS. No person shall be elected or
appointed a director if that person is less than 18 years of age, is of unsound
mind and has been found so by a court, is not an individual, or has the status
of a bankrupt. Directors may, but need not, be Stockholders.

                  (b) Subject to clause (vii) below, each Stockholder agrees to
use all commercially reasonable efforts (including approving all necessary or
advisable amendments to General Partner's certificate of incorporation and/or
bylaws) to cause the board of directors of General Partner (the "BOARD") to
consist of thirteen (13) directors and be composed as follows:

                           (i) The Telcom Investor Group, the Spectrum Investor
         Group and the Columbia Investor Group (or an Investor or group of
         Investors to which Limited Partners of any such Investor Group
         transferred at least a five percent (5%) Percentage Interest and
         expressly transferred such Investor Group's right to designate a

                                       3
<PAGE>

         director under this Agreement (each such Person, an "INVESTOR GROUP
         ASSIGNEE")), collectively, shall be entitled to designate a total of
         one (1) director. Such director shall be selected by the affirmative
         vote of at least two of the three such Investor Groups.

                           (ii) The Telcom Investor Group shall be entitled to
         designate one (1) director.

                           (iii) Motient Sub shall be entitled to designate
         three (3) directors.

                           (iv) TMI Sub shall be entitled to designate three (3)
         directors.

                           (v) MSV Investors, LLC ("MSV INVESTORS") shall be
         entitled to designate three (3) directors.

                           (vi) One director shall be the Chief Executive
         Officer of General Partner (the "CEO").

                           (vii) One director shall be Gary M. Parsons,
         currently the Chairman of MSV LP; PROVIDED, that in the event Mr.
         Parsons resigns or is otherwise removed from the Board, such vacancy
         shall not be filled and thereafter, the Board shall consist of twelve
         (12) directors.

                           (viii) General Partner shall provide each of the
         Columbia Investor Group and the Spectrum Investor Group with notice of
         each meeting of the Board and shall permit one designated
         representative of each of the Columbia Investor Group and the Spectrum
         Investor Group to attend and participate in all discussions of each
         such meeting in a nonvoting capacity, and, in this respect shall give
         the Columbia Investor Group and the Spectrum Investor Group copies of
         all notices, minutes, consents and other material that it provides to
         directors (collectively, the "OBSERVATION RIGHTS"); PROVIDED, that
         General Partner shall also provide the Telcom Investor Group with
         Observation Rights if the Telcom Investor Group does not otherwise have
         the right to select a director and if the director selected pursuant to
         Section 2(b)(i) hereof is not an owner or an Affiliate of the Telcom
         Investor Group; PROVIDED, FURTHER, that the Columbia Investor Group,
         the Spectrum Investor Group and the Telcom Investor Group (if
         applicable) and their designated representatives that attend any Board
         meeting shall, except as otherwise required by law, hold all matters
         discussed at any such meeting in strict confidence as if each such
         Investor Group and its designated representatives were voting members
         of the Board; and PROVIDED FURTHER, that each of the Columbia Investor
         Group, the Spectrum Investor Group and the Telcom Investor Group (if
         applicable) shall be entitled to Observation Rights in accordance with
         the terms of this Section 2(b)(viii) only so long as such Investor
         Group continues to be a holder of capital stock of the General Partner.

                  (c) RESIGNATION. Any director may resign at any time by giving
written notice to the CEO. Such resignation shall take effect at the time
specified in such notice or, if the time be not specified, upon receipt thereof
by the CEO. Unless otherwise specified therein, acceptance of such resignation
shall not be necessary to make it effective. In the event of the death,
disability, resignation or removal of any director, the Stockholder(s) which
designated such director shall designate his or her replacement.

                                       4
<PAGE>

                  Section 3. BOARD MEETING.

                  (a) REGULAR MEETINGS. The Board shall meet no less often than
quarterly, unless otherwise agreed by at least 4/5 of the Board. Such meetings
shall be held on such date as shall be determined by the CEO or a majority of
the Board.

                  (b) OTHER MEETINGS. Other meetings of the Board shall be held
at such times as the Chairman of General Partner (the "CHAIRMAN"), a
vice-chairman of General Partner (a "VICE-CHAIRMAN"), the CEO or a majority of
the Board shall from time to time determine.

                  (c) NOTICE OF MEETINGS. The Secretary of General Partner (the
"SECRETARY") or any person that the Board or the Secretary delegate to act in
the capacity of the Secretary shall give written notice to the CEO, the
President of General Partner (the "PRESIDENT") and each director of each meeting
of the Board, which notice shall state the place, date, time and purpose of such
meeting. Notice of each such meeting shall be given to each director, if by
mail, addressed to him at his residence or usual place of business, at least
five (5) Business Days before the day on which such meeting is to be held, or
shall be sent to him at such place by telecopy, telegraph, cable, or other form
of recorded communication, or may be delivered by electronic mail or be
delivered personally or by telephone not later than forty-eight (48) hours
before the time at which such meeting is to be held; provided, however, that if
any director objects to the holding of such Board meeting at the requested time
and date, such meeting shall be held five (5) Business Days following the date
of such notice. A written waiver of notice, signed by the director entitled to
notice, whether before or after the time of the meeting referred to in such
waiver, shall be deemed equivalent to notice. Neither the business to be
transacted at, nor the purpose of any meeting of the Board, need be specified in
any written waiver of notice thereof. Attendance of a director at a meeting of
the Board shall constitute a waiver of notice of such meeting.

                  (d) PLACE OF MEETINGS. The Board may hold its meetings at such
place or places within or without the State of Delaware as the Chairman or CEO
may from time to time determine, or as shall be designated in the respective
notices or waivers of notice of such meetings.

                  (e) QUORUM AND MANNER OF ACTING.

                  (1) A majority of the directors then in office (or who are
         members of any committee of the Board) shall be present in person or by
         proxy (provided in writing) at any meeting of the Board (or a committee
         thereof, as the case may be) in order to constitute a quorum for the
         transaction of business at such meeting, and the vote of a majority of
         those directors, or members of such committee, present at any such
         meeting at which a quorum is present shall be necessary for the passage
         of any resolution or act of the Board or such committee, except as

                                       5
<PAGE>

         otherwise expressly required by this Agreement or the Investment
         Agreement. In the absence of a quorum for any such meeting, a majority
         of the directors present thereat may adjourn such meeting from time to
         time until a quorum shall be present.

                  (2) ORGANIZATION. At each meeting of the Board, one of the
         following shall act as chairman of the meeting and preside, in the
         following order of precedence:

                           (A)      the Chairman;

                           (B)      the Vice-Chairman; or

                           (C)      any director chosen by a majority of the
                                    directors present.

The Secretary or, in the case of his absence, any person whom the chairman of
the meeting shall appoint shall act as secretary of such meeting and keep the
minutes thereof.

                  (f) COMMITTEES OF THE BOARD. The Board may, by resolution
passed by a majority of the whole Board, designate one or more committees
consisting of four or more directors; PROVIDED, that each committee shall
consist of at least one designee of the Telcom Investor Group, Columbia Investor
Group and Spectrum Investor Group, collectively, as well as one Motient Sub
designee, one TMI Sub designee, and one MSV Investors designee. Except as
otherwise expressly required by this Agreement, any committee of the Board, to
the extent provided in the resolution of the Board designating such committee,
shall have and may exercise all the powers and authority of the Board in the
management of the business and affairs of General Partner, and may authorize the
seal of General Partner to be affixed to all papers which may require it. Each
committee of the Board shall keep regular minutes of its proceedings and report
the same to the Board and upon request of the Stockholders, to the Stockholders.

                  (g) DIRECTORS' CONSENT IN LIEU OF MEETING. Any action required
or permitted to be taken at any meeting of the Board or of any committee thereof
may be taken without a meeting, without prior notice and without a vote, if a
consent in writing, setting forth the action so taken, shall be signed by all
the directors of the Board, in the case of a Board meeting, or all the members
of a committee, in the case of a committee meeting, and such consent is filed
with the minutes of the proceedings of the Board or such committee.

                  (h) ACTION BY MEANS OF TELEPHONE OR SIMILAR COMMUNICATIONS
EQUIPMENT. Any one or more members of the Board, or of any committee thereof,
may participate in a meeting of the Board or such committee by means of
conference telephone or similar communications equipment by means of which all
persons participating in the meeting can hear each other, and participation in a
meeting by such means shall constitute presence in person at such meeting.

                                       6
<PAGE>

                  (i) COMPENSATION. Directors shall not receive any salary or
compensation for their services as directors or as members of committees, except
as authorized by Stockholders holding a majority of the shares of Stock (the
"SHARES"). The directors shall be entitled to be reimbursed for traveling
expenses properly incurred by them in attending meetings of the Board or any
committee thereof. Nothing herein shall preclude any director from serving
General Partner or MSV LP in any other capacity and receiving compensation
therefor.

                  (j) SELECTION OF OFFICERS. Any changes to the officers of
General Partner shall be approved by a vote of the majority of the Board
members.

                  (k) AGREEMENTS WITH LIMITED PARTNERS OR THEIR AFFILIATES.
Notwithstanding the grant of authority to General Partner under Section 6.1 of
the MSV LP Agreement, without the prior written consent of the majority of the
disinterested directors (or, if the majority of the directors are designees of
interested parties, the entire Board) and any prior written consent of Limited
Partners of MSV LP required by the MSV LP Agreement, the Board shall not permit
or cause General Partner or MSV LP to enter into transactions with its Limited
Partners or Affiliates of its Limited Partners except as otherwise permitted in
the Investment Agreement.

                  Section 4. AGREEMENT OF STOCKHOLDERS AND GENERAL PARTNER.

                  (a) AGREEMENT TO VOTE SHARES TO ELECT DIRECTORS. Each
Stockholder hereby agrees to take all action necessary (including voting or
causing to be voted, or acting by written consent with respect to, any and all
Shares held by him or it on the record date for establishing the Stockholders
entitled to vote for the election of directors of General Partner) to cause the
designees of the Telcom Investor Group, the Columbia Investor Group, and the
Spectrum Investor Group, the Motient Sub designees, the TMI Sub designees, the
MSV Investors designees, the CEO and Mr. Parsons to be elected to the Board, in
accordance with the provisions hereof.

                  (b) AGREEMENT TO EFFECT TERRESTAR SPIN-OFF. Each Stockholder
and General Partner hereby agree to use their best efforts as promptly as
possible, and in any event by November 23, 2004, to take such actions as may be
necessary to effect the distribution by MSV LP of all of the outstanding shares
of common stock of TerreStar Networks Inc. ("TERRESTAR") to the limited partners
of MSV LP.

                  Section 5. STOCKHOLDER MEETINGS.

                  (a) REGULAR MEETINGS. The Stockholders shall meet annually,
unless otherwise agreed by the Board. Such meetings shall be held on such date
as shall be determined by the a majority of the Board.

                  (b) SPECIAL MEETINGS. Special meetings of the Stockholders
shall be held at such times as the Board, the President or a majority in
interest of the Stockholders shall from time to time determine.

                  (c) NOTICE OF MEETINGS. The Secretary shall give written
notice to the President and each Stockholder of each meeting of the
Stockholders, which notice shall state the place, date, time and purpose of such
meeting. Notice of each such meeting shall be given to each Stockholder, if by
mail, to the address set forth with respect to such Stockholder in SCHEDULE I,
at least five (5) Business Days before the day on which such meeting is to be

                                       7
<PAGE>

held, or shall be sent to such Stockholder by telecopy, telegraph, cable, or
other form of recorded communication, or be delivered personally or by telephone
not later than forty-eight (48) hours before the time at which such meeting is
to be held; PROVIDED, HOWEVER, that if any Stockholder objects to the holding of
such Stockholder meeting at the requested time and date, such meeting shall be
held five (5) Business Days following the date that such notice was given. A
written waiver of notice, signed by the Stockholder entitled to notice, whether
before or after the time of the meeting referred to in such waiver, shall be
deemed equivalent to notice. Neither the business to be transacted at, nor the
purpose of any meeting of the Stockholders need be specified in any written
waiver of notice thereof. Attendance of a Stockholder at a meeting of the
Stockholders shall constitute a waiver of notice of such meeting.

                  (d) PLACE OF MEETINGS. The Stockholders may hold their
meetings at such place or places within or without the State of Delaware as the
President may from time to time determine, or as shall be designated in the
respective notices or waivers of notice of such meetings.

                  (e) QUORUM AND MANNER OF ACTING. The Stockholders holding the
majority of the Shares shall be present in person or by proxy at any meeting of
the Stockholders in order to constitute a quorum for the transaction of business
at such meeting, and, except as otherwise provided herein or in the Investment
Agreement, the vote of those Stockholders holding a majority of the Shares,
present at any such meeting at which a quorum is present, shall be necessary for
the passage of any resolution or act of the Stockholders, except as otherwise
expressly required by this Agreement. In the absence of a quorum for any such
meeting, holders of a majority of the Shares present thereat may adjourn such
meeting from time to time until a quorum shall be present.

                  (f) STOCKHOLDERS' CONSENT IN LIEU OF MEETING. Any action
required or permitted to be taken at any meeting of the Stockholders may be
taken without a meeting, without prior notice and without a vote, if a consent
in writing, setting forth the action so taken, shall be signed by the
Stockholders holding the requisite number of Shares for the taking the relevant
action and such consent is filed with the minutes of the proceedings of the
Stockholders.

                  (g) ACTION BY MEANS OF TELEPHONE OR SIMILAR COMMUNICATIONS
EQUIPMENT. Any one or more Stockholders may participate in a meeting of the
Stockholders by means of conference telephone or similar communications
equipment by means of which all persons participating in the meeting can hear
each other, and participation in a meeting by such means shall constitute
presence in person at such meeting.

                  Section 6. ASSIGNMENT; RESTRICTION ON TRANSFER. The rights of
the Stockholders to designate directors hereunder may not be transferred, except
in accordance with Section 2(b)(i).

                                       8
<PAGE>

                  Section 7. TRANSFER OF SHARES. The Stockholders each undertake
to take such actions and execute such documents as may be necessary to insure
that the proportionate ownership of General Partner at all times reflects the
then-current proportional ownership of Limited Partnership Interests in MSV LP,
excluding for this purpose, any Limited Investor. In furtherance of the
foregoing, except for Transfers made simultaneously with permitted transfers of
Limited Partnership Interests made in accordance with the terms of Section 8 of
this Agreement, each Stockholder agrees not to, directly or indirectly, sell,
assign, transfer, pledge, encumber, hypothecate, mortgage or otherwise dispose
of, either voluntarily or involuntarily (or to enter into any contract, option
or other arrangement or understanding to do any of the foregoing) (a
"TRANSFER"), any Shares; PROVIDED, HOWEVER, that TMI Sub shall be permitted to
pledge its Shares pursuant to the Pledge Agreement. In addition, each
Stockholder hereby undertakes to, at the same time that it transfers any of its
Limited Partnership Interests, Transfer its Shares (or the same portion thereof
as the Limited Partnership Interests being transferred bear to its total Limited
Partnership Interests) to the purchaser or assignee of any of its Limited
Partnership Interests in accordance with Section 8 of this Agreement. Following
a Transfer of such Shares, such Shares shall remain subject to the provisions of
this Agreement, and the transferee shall execute and deliver to General Partner
a written agreement to be bound by this Agreement in form and substance
reasonably satisfactory to General Partner. Notwithstanding the foregoing,
except as set forth in Section 2(b)(i) with respect to Transfers to an Investor
Group Assignee, in connection with transfers of Limited Partnership Interests
pursuant to Sections 8.2(c) or (d) of this Agreement, no transferee shall have
the right to designate directors pursuant hereto.

                  Section 8. TRANSFERS, ADMISSION OF LIMITED PARTNERS AND
CONVERSION.

                  Section 8.1 ADDITIONAL ISSUANCES OF INTERESTS.

                  (a) In order to raise capital for MSV LP operations or to
acquire assets, to redeem or retire MSV LP debt, or for any other valid MSV LP
purposes, General Partner may, subject to the provisions of this Section 8.1,
from time to time determine that it is in the best interests of MSV LP to cause
MSV LP to issue additional interests in MSV LP to the Limited Partners or other
Persons and to admit such other Persons to MSV LP as Additional Limited Partners
pursuant to Section 8.4. General Partner shall determine the consideration for
and the terms and conditions with respect to any future issuance of interests in
MSV LP.

                  (b) Subject to clause (h) below, General Partner shall not
issue any interests in MSV LP unless it first delivers to each Limited Partner
(each such Person being referred to in this Section 8.1 as a "BUYER") a written
notice (the "NOTICE OF PROPOSED ISSUANCE") specifying the type and amount of
such interests that MSV LP then intends to issue (the "OFFERED INTERESTS"), all
of the material terms, including the price (cash or non-cash) upon which MSV LP
proposes to issue the Offered Interests and stating that the Buyers shall have
the right to purchase the Offered Interests in the manner specified in this
Section 8.1 for the same price per share and in accordance with the same terms
and conditions specified in such Notice of Proposed Issuance, PROVIDED, that if
such price consists of non-cash consideration, a Buyer may purchase the Offered
Interest with the same type and amount of non-cash consideration described in
such Notice of Proposed Issuance or, may instead, pay for such Offered Interests
with the cash equivalent of such price.

                                       9
<PAGE>

                  (c) During the ten (10) consecutive day period commencing on
the date MSV LP delivers to all of the Buyers the Notice of Proposed Issuance
(the "TEN DAY PERIOD"), the Buyers shall have the option to purchase up to all
of the Offered Interests at the same price and upon the same terms and
conditions specified in the Notice of Proposed Issuance. Each Buyer electing to
purchase Offered Interests must give written notice of its election to General
Partner prior to the expiration of the Ten Day Period.

                  (d) Each Buyer shall have the right to purchase up to that
percentage of the Offered Interests equal to the Percentage Interest then held
by such Buyer. The amount of such Offered Interests that each Buyer is entitled
to purchase under this Section 8.1 shall be referred to as its "PROPORTIONATE
SHARE."

                  (e) Each Buyer shall have a right of oversubscription such
that if any other Buyer fails to elect to purchase his or its full Proportionate
Share of the Offered Interests, the other Buyer(s) shall, among them, have the
right to purchase up to the balance of such Offered Interests not so purchased.
The Buyers may exercise such right of oversubscription by electing to purchase
more than their Proportionate Share of the Offered Interests by so indicating in
their written notice given during the Ten Day Period. If, as a result thereof,
such oversubscription elections exceed the total number of the Offered Interests
available in respect to such oversubscription privilege, the oversubscribing
Buyers shall be cut back with respect to oversubscriptions on a pro rata basis
in accordance with their respective Proportionate Share or as they may otherwise
agree among themselves.

                  (f) If all of the Offered Interests have not been purchased by
the Buyers pursuant to the foregoing provisions, then General Partner shall have
the right, until the expiration of one hundred eighty (180) consecutive days
commencing on the first day immediately following the expiration of the Ten Day
Period, to issue the Offered Interests not purchased by the Buyers at not less
than, and on terms no more favorable in any material respect to the purchaser(s)
thereof than, the price and terms specified in the Notice of Proposed Issuance.
If such remaining Offered Interests are not issued within such period and at
such price and on such terms, the right to issue in accordance with the Notice
of Proposed Issuance shall expire and the provisions of this Agreement shall
continue to be applicable to the Offered Interests.

                  (g) Notwithstanding the foregoing, the rights described in
this Section 8.1 shall not apply with respect to the issuance of Excluded
Securities.

                  (h) Notwithstanding the foregoing, General Partner may proceed
with the issuance of interests in MSV LP without first following the procedures
in clauses (b)-(f) above, provided that the purchaser of such interests (the
"NEW PURCHASER") agrees in writing to take such interests subject to the
provisions of this Section 8.1(h). In such event the following provisions shall
apply:

                                       10
<PAGE>

                           (i) Within ten (10) days following the issuance of
such interests, General Partner or the New Purchaser shall issue to each Buyer a
written notice (the "NOTICE OF ISSUANCE") specifying the type and amount of such
interests that MSV LP has issued (the "ISSUED INTERESTs"), all of the material
terms, including the price (the "ISSUED INTEREST PRICE") at which MSV LP issued
the Issued Interests and stating that the Buyers shall have the right to
purchase Issued Interests in the manner specified below for the same price per
Unit and in accordance with the same terms and conditions specified in such
Notice of Issuance.

                           (ii) During the ten (10) consecutive day period
commencing on the date MSV LP or the New Purchaser delivers to all of the Buyers
the Notice of Issuance (the "ISSUANCE TEN DAY PERIOD"), the Buyers shall have
the option to purchase up to all of the Issued Interests for the same type and
amount per Issued Interest of cash or non-cash consideration paid by the New
Purchaser or cash in an amount equivalent in value to the Issued Interest Price
and upon the same terms and conditions specified in the Notice of Issuance. Each
Buyer electing to purchase Issued Interests must give written notice of its
election to the deliverer of the Notice of Issuance prior to the expiration of
the Issuance Ten Day Period.

                           (iii) Each Buyer shall have the right to purchase
from the New Purchaser up to that percentage of the Issued Interests equal to
the Proportionate Share held by such Buyer immediately prior to the issuance of
the Issued Interests.

                           (iv) Each Buyer shall have a right of
oversubscription such that if any other Buyer fails to elect to purchase his or
its full Proportionate Share of the Issued Interests, the other Buyer(s) shall,
among them, have the right to purchase up to the balance of such Issued
Interests not so purchased. The Buyers may exercise such right of
oversubscription by electing to purchase more than their Proportionate Share of
the Issued Interests by so indicating in their written notice given during the
Issuance Ten Day Period. If, as a result thereof, such oversubscription
elections exceed the total number of the Issued Interests available in respect
to such oversubscription privilege, the oversubscribing Buyers shall be cut back
with respect to oversubscriptions on a pro rata basis in accordance with their
respective Proportionate Share or as they may otherwise agree among themselves.

                           (v) Any Issued Interests that have not been purchased
by the Buyers pursuant to the foregoing provisions shall remain owned by the New
Purchaser.

                           (vi) Notwithstanding anything in this clause (h) to
the contrary, in the event the Buyers elect, within the Issuance Ten Day Period,
to purchase less than all of the Issued Interests then, in lieu of the Buyers
purchasing Issued Interests from the New Purchaser, General Partner may elect to
issue directly to such Buyers, for the same type and amount per Issued Interest
of cash or non-cash consideration paid by the New Purchaser or cash in an amount
equivalent in value to the Issued Interest Price, an equivalent amount of
additional securities that are identical to the Issued Interests in all material
respects.

                                       11
<PAGE>

                  Section 8.2 TRANSFERS. No Limited Partner may assign or
transfer all or any part of its Limited Partnership Interest to any Person,
except in compliance with the following:

                  (a) RIGHT OF FIRST REFUSAL. In the event that a Limited
Partner (a "SELLING PARTY") proposes to transfer all or a portion of its Limited
Partnership Interest to any third party, other than in accordance with Section
8.2(c) or (d), pursuant to a bona fide offer, such Selling Party will provide
notice of such proposed transfer (including the identity of the proposed
purchaser of such interest, the amount of interests proposed to be transferred
and the proposed terms thereof) (the "TRANSFER NOTICE"), at least fifteen (15)
Business Days prior to the proposed transfer, to each other Limited Partner,
whereupon each other Limited Partner shall have the right to purchase, at the
same price and upon the same terms and conditions set forth in the Transfer
Notice, a pro rata portion of such interest based upon such Limited Partner's
portion of the Percentage Interests held by all Limited Partners other than the
Selling Party. Except as set forth in the next sentence, the purchase price
shall be payable in cash. In the event that the Transfer Notice specifies the
payment of consideration other than cash, the purchase price for purposes of
this Section 8.2(a) shall either be (x) the cash equivalent of such
consideration, determined by General Partner in good faith or (y) to the extent
the participating Limited Partner elects, the same type and amount of non-cash
consideration that is proposed to be paid as described in the Transfer Notice.
The Transfer Notice shall constitute an irrevocable offer by the Selling Party
to sell to the other Limited Partners such interests at the price and on the
terms as contained in such Transfer Notice. Each Limited Partner desiring to
participate in such purchase shall provide the Selling Party and each other
Limited Partner notice of its agreement to participate (the "PARTICIPATION
NOTICE") within ten (10) Business Days of receipt of the Transfer Notice
specifying such participation and whether and the extent to which such Limited
Partner wishes to acquire any remaining, unallocated portion of the proposed
transfer (the "UNALLOCATED PORTION"). In the event that one or more of the other
Limited Partners do not provide a timely Participation Notice, the Unallocated
Portion shall be allocated in pro rata proportion to the Percentage Interest
held by each of the Limited Partners who submits a Participation Notice to the
extent of such Limited Partner's indicated willingness to acquire any
Unallocated Portion as provided in such Limited Partners' Participation Notice.
The Participation Notice shall be deemed to be an irrevocable commitment to
purchase from the Selling Party, at the price (or the cash equivalent thereof)
and on the terms as contained in the Transfer Notice, the amount of the
interests that such Limited Partner specifies in the Participation Notice. In
the event that the Limited Partners are not willing to purchase all of the
interests offered pursuant to the Transfer Notice, and the amount of interests
which the Selling Party has offered to sell pursuant to the Transfer Notice less
the amount of interests the Limited Partners are willing to accept is less than
the minimum amount of interests which the offeror is willing to purchase
pursuant to the bona fide offer described in the Transfer Notice, then the
Limited Partners shall be deemed to have rejected the offer contained in the
Transfer Notice in its entirety and the Selling Party shall be permitted to
proceed with the sale described in the Transfer Notice. In the event that the
Limited Partners shall have accepted all or part of the interests offered
pursuant to the Transfer Notice (and shall not have been deemed to have rejected

                                       12
<PAGE>

the offer in its entirety as described in the immediately preceding sentence),
then the Selling Party shall sell to such Limited Partners such interests as
have been accepted by such Limited Partners as specified in such Limited
Partner's Participation Notice on the terms contained in the Transfer Notice.
Any interests not sold to the Limited Partners pursuant to the preceding
sentence may be sold to a third party, including the original offeror, at a
price not lower than, and on such other terms and conditions not more favorable
to such third party than, those contained in the original Transfer Notice, at
any time within one hundred eighty (180) days after the expiration of the offer
required by this Section 8.2(a). In the event the interests are not transferred
by the Selling Party on such terms during such one hundred eighty (180) day
period, the restrictions of this Section 8.2(a) shall again become applicable to
any transfer of interests by the Selling Party.

                  (b) TAG ALONG RIGHTS.

                           (i) GENERAL. No Selling Party may transfer (other
than pursuant to Section 8.2(c) or 8.2(d)) Limited Partnership Interests held
by such Selling Party to any Person, unless the terms and conditions of such
transfer shall include an offer by the third party transferee to the other
Limited Partners (each, a "TAG ALONG PARTICIPANT"), at a price calculated using
the same methodology used to calculate the price of the Selling Party's Limited
Partnership Interest taking into account the relative capital accounts and
distribution rights of the Tag Along Participants (such price, the "TAG ALONG
PRICE") and on the same terms and conditions as the Selling Party has agreed to
sell its Limited Partnership Interest, to include in the transfer to the third
party transferee a portion of Limited Partnership Interests.

                           (ii) OBLIGATION OF TRANSFEREE TO PURCHASE. The
third-party transferee of the Selling Party shall purchase from each Tag Along
Participant the portion of such Tag Along Participant's Limited Partnership
Interest that such Tag Along Participant desires to sell, provided that such
portion does not exceed the Maximum Tag Along Portion (as defined below) and, if
such portion exceeds the Maximum Tag Along Portion, the transferee shall
purchase only the Maximum Tag Along Portion. For purposes hereof, the term
"MAXIMUM TAG ALONG PORTION" means a portion of a Tag Along Participant's Limited
Partnership Interest the price of which (based on the Tag Along Price of such
Limited Partnership Interest) equals the total original price proposed to be
paid by the transferee for the Selling Party's Limited Partnership Interest
multiplied by a fraction, the numerator of which is the Tag Along Price of such
portion which such Tag Along Participant desires to include in such sale and the
denominator of which is the aggregate Tag Along Price of the Limited Partnership
Interests that the Selling Party and each Tag Along Participant desires to
include in such sale.

                           (iii) EXERCISE. The tag-along right may be exercised
by each Tag-Along Participant by delivery of a written notice to the
Selling Party (the "TAG ALONG NOTICE") within 15 calendar days following receipt
of the Transfer Notice. The Tag Along Notice shall state the portion of a
Limited Partnership Interest that such Tag Along Participant wishes to include
in such transfer to the transferee. Upon the giving of a Tag Along Notice, such
Tag Along Participant shall be entitled and obligated to sell the portion of its
Limited Partnership Interest set forth in the Tag Along Notice, to the
transferee on the terms and conditions set forth in the Transfer Notice (the
"TRANSFEREE TERMS"); provided, however, the Selling Party shall not consummate

                                       13
<PAGE>

the sale of any Limited Partnership Interest offered by it if the transferee
does not purchase all Limited Partnership Interests which each Tag Along
Participant is entitled and desires to sell pursuant hereto. After expiration of
the 15 calendar-day period referred to above, if the provisions of this Section
have been complied with in all respects, the Selling Party and each Tag Along
Participant that delivered a Tag Along Notice shall transfer the Limited
Partnership Interests determined in accordance with Section 8.2(b)(ii) to the
transferee on the Transferee Terms on the sale date proposed in the Transfer
Notice (or such other date within sixty (60) days of such proposed sale date as
may be agreed among the participants in such transfer).

                           (iv) SEVERAL LIABILITY. Anything to the contrary
contained herein notwithstanding, the Selling Party agrees to use its
reasonable good faith efforts to seek to ensure that the applicable Transferee
Terms provide for several, and not joint, liability, with respect to the
indemnification and comparable obligations contained within such Transferee
Terms.

                           (v) The tag-along rights set forth in this Section
8.2(b) shall not be deliberately circumvented by a Selling Party under
circumstances where the other Limited Partners would have a reasonable
expectation that such tag-along rights would apply.

                  (c) Subject to Sections 8.2(e), (f) and (g), a Limited Partner
may at any time and from time to time (i) transfer all or part of such Limited
Partner's Limited Partnership Interest to any of such Limited Partner's Family
Members provided that such Limited Partner shall provide the other Partners
notice of the identity of such Family Member transferee, (ii) transfer all or
part of its Limited Partnership Interest to its members, partners, shareholders
or other equity holders, as the case may be ("DISTRIBUTEE"), pro-rata in
accordance with the governing documents of the Limited Partner, and without
consideration, or (iii) transfer all or part of such Limited Partner's Limited
Partnership Interest to a Control Party of such Limited Partner; PROVIDED, that
such Limited Partner and Control Party agree with MSV LP in writing that such
Control Party shall transfer such Limited Partnership Interest back to such
Limited Partner immediately upon such Person ceasing to be a Control Party of
such Limited Partner. A Limited Partner may at any time and from time to time
pledge or hypothecate, in connection with its bona fide financing arrangements
(including, in the case of Motient, under its current guaranteed bank
facilities), its Limited Partnership Interest, PROVIDED, that upon foreclosure
or other execution of the pledge or hypothecation, any assignment or transfer
shall be subject to Sections 8.2(e), (f) and (g). Subject to Sections 8.2(e),
(f) and (g) and Section 8.6, a Limited Partner that is a member of the Telcom
Investor Group, Columbia Investor Group or Spectrum Investor Group may at any
time and from time to time transfer all or part of its Limited Partnership
Interest to another Limited Partner that is a member of the Telcom Investor
Group, Columbia Investor Group or Spectrum Investor Group.

                                       14
<PAGE>

                  (d) Each of TMI Sub, Motient Sub and MSV Investors shall have
the right, subject to Sections 8.2(a), (e), (f), and (g), to assign or transfer
its interest in MSV LP to any Person owning 10% or more of the outstanding
common stock of BCE Inc., Motient or SkyTerra Communications, Inc.,
respectively, and each other Limited Partner shall have the right, subject to
Sections 8.2(a), (e), (f), and (g), to assign or transfer its interest in MSV LP
to any Person owning ten percent (10%) or more of the ownership interests in
such Limited Partner; PROVIDED that in the case of a transfer by TMI Sub, such
transferee agrees to be bound by the terms and conditions of (i) the
Non-Interference Agreement, dated as of November 26, 2001, between BCE Inc. and
MSV LP (as amended, supplemented or modified from time to time, the
"NON-INTERFERENCE AGREEMENT") applicable to BCE Inc., (ii) the Stockholders
Agreement, dated as of November 26, 2001, by and among TMI, MSV LP, Canadian
Holdco and Canadian License Co. and (iii) the Pledge Agreement.

                  (e) In addition to any other requirements of this Agreement
relating to a transfer of Limited Partnership Interests, no Limited Partnership
Interest shall be transferred or assigned unless the transferee (i) executes an
instrument satisfactory to General Partner accepting all of the terms and
conditions relating to a Limited Partner set forth in this Agreement and the MSV
LP Agreement, (ii) pays any reasonable expenses of MSV LP incurred in connection
with such transfer or assignment (including, without limitation, attorney's
fees) and (iii) is either an "accredited investor" (as defined in Rule 501
promulgated under the Securities Act of 1933, as amended (the "SECURITIES ACT"))
or provides an opinion of counsel reasonably acceptable to General Partner that
the transfer will not require registration under the Securities Act.

                  (f) Notwithstanding any other provisions of this Agreement to
the contrary, General Partner may prohibit any proposed transfer if, in the
reasonable determination of the General Partner, such transfer would (i) result
in the close of MSV LP's taxable year with respect to all Limited Partners, in
the termination of MSV LP within the meaning of ss. 708(b) of the Code or in the
termination of its status as a partnership under the Code, (ii) cause MSV LP to
be in violation of any applicable state or federal securities laws or (iii)
result in an interest in MSV LP being held by a Person whose participation in
the ownership of MSV LP would be detrimental to MSV LP; PROVIDED, HOWEVER, that
no transfer made pursuant to Section 8.2(c) hereof shall be deemed detrimental
to MSV LP.

                  (g) To the extent that any regulatory approval, notification
or other submission or procedure is required or customarily provided in
connection with the exercise of any right or obligations as set forth in this
Agreement or the MSV LP Agreement with respect to the transfer or assignment of
interests in MSV LP (including, but not limited to, FCC approvals (if required),
filings under the HSR Act and applicable securities laws), such transfer or
assignment pursuant to this Agreement will be delayed and will only take place
after such approval, notification or other submission or procedure has been
obtained, submitted or completed, as determined by General Partner.

                  (h) In addition to any other restrictions regarding TMI Sub's
right to transfer the Limited Partnership Interests held by it contained herein
or in any Ancillary Agreement, TMI Sub shall not be permitted to transfer its
Limited Partnership Interests except to a Person (or an Affiliate of such
Person) that is also simultaneously acquiring TMI's direct or indirect ownership
interests in Canadian Holdco and Canadian License Co. Any purported transfer of
TMI Sub's Limited Partnership Interests in contravention of this subsection (h)
shall be void and of no effect.

                                       15
<PAGE>

                  (i) Any transfer of Limited Partnership Interests hereunder
shall be deemed to include a proportional transfer of the transferor's Units and
Capital Account, adjusted for all prior allocations and distributions with
respect to the transferred Capital Account for purposes of Articles VII and VIII
of the MSV LP Agreement.

                  (j) Intentionally Omitted.

                  (k) For purposes of this Agreement, the sale or transfer of
any equity or other ownership interests in any Intervening Entity (an
"INTERVENING ENTITY OWNERSHIP CHANGE") shall be deemed to constitute a transfer
of the aggregate Limited Partnership Interests held by that Limited Partner
multiplied by a fraction, the numerator of which is the percentage ownership of
the Intervening Entity so sold or transferred and the denominator of which is
100%. If such a deemed transfer of Limited Partnership Interests occurs without
compliance with or as permitted by the provisions of Section 8.2(a) though
8.2(i) (as applicable) of this Agreement then, without limiting the rights of
MSV LP or the other Partners at law or in equity, all of the Limited Partners
(other than the Limited Partner which is so deemed to have transferred Limited
Partnership Interests) shall have the right to purchase the Limited Partnership
Interests so deemed transferred as if such Limited Partnership Interests were
being offered for sale pursuant to the provisions of Section 8.2(a) (the
provisions of which are hereby incorporated by reference, mutatis mutandis) for
the same amount of consideration to be given to the Intervening Entity or its
owners, in respect of the Intervening Entity Ownership Change.

                  (l) Any attempted transfer of Units or Limited Partnership
Interests in violation of this Agreement shall be void and of no effect.

                  Section 8.3  ADMISSION OF SUBSTITUTED LIMITED PARTNERS.

                  (a) An assignee or transferee of an interest in MSV LP shall
not be admitted to MSV LP as a substituted Limited Partner until (i) such
assignee or transferee and transferring Limited Partner has complied with all of
the conditions and procedures set forth in Section 8.2, (ii) such assignee or
transferee has confirmed in writing to General Partner that it has reviewed the
terms and conditions of this Agreement, the MSV LP Agreement, the Investment
Agreement and each of the Ancillary Agreements including, without limitation,
the events of default, remedy and forfeiture provisions of the Pledge Agreement,
and (iii) payment of any reasonable expenses of MSV LP incurred in connection
with such admission (including, without limitation, attorney's fees). Such
assignee or transferee shall automatically be admitted to MSV LP as a Limited
Partner following satisfaction of the provisions of this Section 8.3(a).

                                       16
<PAGE>

                  (b) A Person who acquires any Limited Partnership Interests of
a Limited Partner pursuant to Section 8.2 but who is not admitted as a
substituted Limited Partner pursuant to Section 8.3(a) shall be entitled only to
allocations and distributions with respect to such acquired Limited Partnership
interests in accordance with this Agreement, but shall have no right to vote or
give consent hereunder, to obtain any information or accounting of the affairs
of MSV LP, shall not solely as a result of its acquisition of such Limited
Partnership Interests obtain or have the right to obtain any shares in General
Partner, shall not be entitled to inspect the books or records of MSV LP and
shall not have any rights of a Limited Partner under the Delaware Act, this
Agreement or the MSV LP Agreement.

                  (c) A transferor of interests shall remain a Limited Partner
of MSV LP with respect to such transferred interests until such time, if ever,
as the transferee of such interests is admitted as a substituted Limited Partner
in accordance with this Agreement.

                  Section 8.4 ADMISSION OF ADDITIONAL LIMITED PARTNERS. A Person
(other than a current Limited Partner) who purchases from MSV LP interests
issued pursuant to Section 8.1 shall be admitted to MSV LP as an Additional
Limited Partner upon furnishing to MSV LP (a) a subscription agreement, in form
satisfactory to the General Partner, which agreement shall include an acceptance
by such Person of all the terms and conditions of this Agreement, and (b) such
other documents as the General Partner deems necessary or advisable. Such
admission shall become effective on the date that the General Partner determines
that such conditions have been satisfied.

                  Section 8.5 CORPORATE CONVERSION; DRAG-ALONG RIGHTS.

                  (a) At the General Partner's discretion, MSV LP shall be
converted into corporate form ("MSV") by merger, statutory conversion or any
other method set forth in such consent (the "CORPORATE CONVERSION"). If the
Corporate Conversion is in connection with an initial public offering of MSV
LP's (or its successor's) securities, the outstanding interests in MSV LP shall
be converted into common stock of MSV in accordance with the Percentage
Interests represented by such Limited Partnership Interests, and each holder of
such interests shall take such steps as may be reasonably requested by the
General Partner in connection therewith, whereupon the rights and obligations of
the Limited Partners hereunder, including, without limitation, those arising
under Article 6, shall cease and have no further force and effect. If a
Corporate Conversion is approved for any purpose other than in connection with
an initial public offering of MSV LP's (or its successor's) securities, (i) the
respective outstanding interests of MSV LP shall be converted into securities of
MSV which track, as closely as practicable, the economic, voting and other
rights represented by such outstanding interests immediately prior to the
Corporate Conversion and (ii) the holders of such interests shall enter into a
shareholders agreement and such other agreements and the organizational
documents of MSV will contain such provisions as may be necessary, to allow MSV
to mimic, as closely as practicable, the governance and other operating
provisions of the MSV LP Agreement, including, without limitation, an agreement
by all shareholders holding stock with special voting, economic or other rights

                                       17
<PAGE>

to convert such stock into common stock immediately prior to the initial public
offering of MSV securities on a basis similar to that contemplated by the second
sentence of this Section 8.5(a). In effecting a Corporate Conversion, the
General Partner shall cooperate in good faith with TMI Sub to reduce any adverse
tax consequences to TMI Sub resulting from the Corporate Conversion. In the
event MSV LP effectuates a Corporate Conversion, the Stockholders who are
blocker C corporations ("BLOCKER C CORPORATIONS") shall, if so requested by
their parents, in a reorganization intended to be tax-free, be merged with and
into or contributed to MSV LP's successor corporation in exchange for shares of
the successor corporation, such that the stockholders of the applicable Blocker
C Corporations become direct stockholders of the successor corporation upon the
same terms as would be applicable to the Blocker C Corporations had such merger
or contribution not occurred, and, if such Corporate Conversion is effected
other than in connection with an initial public offering of MSV LP's (or its
successor's) securities, such stockholders shall enter into a stockholders'
agreement and such other agreements as may be necessary to allow MSV to mimic,
as closely as practicable, the governance and other operating provisions of MSV
LP's existing governance documents. The consummation of any such merger or
contribution shall be subject to the receipt or waiver of any third-party or
government consents, approvals and authorizations as may be necessary or
advisable in connection therewith, including, but not limited to, expiration or
termination of any applicable waiting period under the HSR Act, and shall be
effected pursuant to a merger or contribution agreement reasonably acceptable to
MSV LP or the successor corporation, as applicable; provided that such Blocker C
Corporation shall be a corporation permitted under applicable law and its
governing instruments to effectuate such merger or contribution transaction and
shall have represented and warranted to MSV LP or the successor corporation that
such Blocker C Corporation has no assets or liabilities other than its Limited
Partnership Interests and Shares and its rights and obligations under this
Agreement, the MSV LP Agreement, the Investment Agreement, the Pledge Agreement
and the Voting Agreement.

                  (b) If the Required Majority determines to transfer or
exchange (in a merger, business combination or otherwise) in one or a series of
related bona fide arm's-length transactions (collectively, the "DRAG-ALONG
TRANSACTION") to an unrelated and unaffiliated third party all of the Limited
Partnership Interests held by such Limited Partners, then, upon thirty (30)
days' written notice to the other Limited Partners and MSV LP (the "DRAG-ALONG
NOTICE"), which notice shall include reasonable details of the proposed
transaction, including the consideration to be received by the Limited Partners,
each other Limited Partner and holder of Limited Partnership Interests shall be
obligated to, and shall sell, transfer and deliver, or cause to be sold,
transferred and delivered, to such third party, all of its Limited Partnership
Interests in the same transaction at the closing thereof (and will deliver such
Limited Partnership Interests free and clear of all liens, claims, or
encumbrances except this Agreement or the MSV LP Agreement) (or shall vote in
favor of or consent to any transaction requiring the vote or consent of Limited
Partners), and shall otherwise cooperate in the consummation of such
transaction, and the consideration to be paid to the Limited Partners shall be
deemed to be Capital Proceeds and shall be distributed to the Limited Partners
pursuant to Section 8.6 of the MSV LP Agreement as if such transaction were a
Capital Event. In the event a Drag-Along Transaction is initiated by the
Investors, unless the consideration to be received by the Limited Partners is

                                       18
<PAGE>

based solely on the respective Percentage Interests held by such Limited
Partners, after the second anniversary date of the Subsequent Closing, each of
Motient and TMI shall have thirty (30) days from receipt of the Drag-Along
Notice to make, or cause a third party to make, a bona fide offer that is no
less favorable to the Investors and the other Limited Partners than the terms,
conditions and consideration of the Drag-Along Transaction described in such
Drag-Along Notice and which will be consummated within thirty (30) days after
such offer is made.

                  Section 8.6 ACTIONS REQUIRING CONSENT. Without the prior
written consent of the Required Majority, no Stockholder or Limited Partner
(including any Affiliate of such Stockholder or Limited Partner) shall acquire
in any transaction or series of related transactions direct or indirect
ownership of more than 49% of (a) the outstanding shares of Stock or (b) the
outstanding Units (including in each case any Stock or Units attributable to
unexercised options or warrants or other similar securities owned by such
Stockholder or Limited Partner or their Affiliates).

                  Section 9. LEGENDS. Each Stockholder consents to General
Partner inserting appropriate legends referencing the restrictions and
obligations contained in this Agreement on the certificates representing the
Shares held by the Stockholders on or after the date of this Agreement.

                  Section 10. STOCKHOLDERS' REPRESENTATION. Each Stockholder
hereby represents that, notwithstanding anything herein to the contrary, it has
no plan or intention to consummate any Transfer of Shares.

                  Section 11. MISCELLANEOUS.

                  (a) REPRESENTATION. No Stockholder is a party to any other
agreement, other than the MSV LP Agreement, the Investment Agreement, the Pledge
Agreement and that certain Voting Agreement, dated as of the date hereof (the
"VOTING AGREEMENT"), by and among the Spectrum Investor Group, the Telcom
Investor Group, the Columbia Investor Group, TMI Sub and MSV Investors, with
respect to the transfer or disposition of voting rights with respect to any
Shares.

                  (b) SEVERABILITY. Should any one or more of the provisions of
this Agreement be determined to be illegal or unenforceable, each other
provision of this Agreement shall be given effect separately from the provision
or provisions determined to be illegal or unenforceable and shall not be
affected thereby.

                  (c) NO WAIVER. No failure or delay on the part of any party in
exercising any right, power or remedy hereunder shall operate as a waiver
thereof; nor shall any single or partial exercise of any such right, power or
remedy preclude any other or further exercise thereof or the exercise of any
other right, power or remedy hereunder.

                  (d) ENTIRE AGREEMENT. This Agreement, the Investment
Agreement, the MSV LP Agreement and the Purchase Agreement, together with the
exhibits thereto constitute the entire agreement among the parties pertaining to
the subject matter hereof and supersede all prior agreements and understandings
of the parties in connection herewith, including but not limited to the November
2001 Stockholders' Agreement.

                                       19
<PAGE>

                  (e) AMENDMENT AND MODIFICATION. This Agreement may be amended,
modified and supplemented only by written agreement of the holders of a majority
of the Shares (or, in the event the provision to be amended contains language
requiring the consent of a greater percentage of the Shares, such greater
percentage); PROVIDED, HOWEVER, that any amendment, modification or supplement
to this Agreement that would adversely affect any individual Stockholder, or
group of Stockholders, in a manner different than its effect on other
Stockholders, shall require the prior written consent of such Stockholder(s).
Notwithstanding the foregoing, if MSV LP shall admit any new limited partner and
the Board shall determine that the Board should be expanded to allow for
representation on the Board by such new limited partner, this Agreement may be
amended by the written agreement of the holders of a majority of the Shares to
provide for one or more additional directors (the number of such additional
directors to be reasonably proportionate to the Percentage Interest in MSV LP
held by such new limited partner), which director(s) shall be designated by such
new limited partner.

                  (f) REMEDIES. The parties acknowledge and agree that the
breach of any of the terms of this Agreement will cause irreparable injury for
which an adequate remedy at law is not available. Accordingly, it is agreed that
each party hereto shall be entitled to an injunction, restraining order or other
equitable relief to prevent breaches of this Agreement and to enforce
specifically the terms and provisions hereof in any court of competent
jurisdiction in the United States or any state thereof, without the requirement
of the posting of any bond. Such remedies shall be cumulative and non-exclusive
and shall be in addition to any other rights and remedies the parties may have
under this Agreement.

                  (g) NOTICES. All notices provided for in this Agreement shall
be in writing, duly signed by the party giving such notice, and shall be
delivered personally, sent by a nationally recognized overnight courier,
telecopied or mailed by registered or certified mail, as follows:

                           (i) If given to General Partner, at General Partner's
mailing address set forth below:

                  Mobile Satellite Ventures GP Inc.
                  10802 Parkridge Boulevard
                  Reston, Virginia 20191-5416
                  Fax:  (703) 390-2770
                  Attention:  General Counsel

                  with a copy to each Stockholder as set forth in clause (ii)
below.

                           (ii) If given to any Stockholder, at the address set
forth on SCHEDULE I hereof (or as modified from time to time by a Stockholder
upon written notice to General Partner).

                                       20
<PAGE>

                  Notices delivered personally to an addressee or sent by
overnight courier shall be deemed to have been given upon such delivery. Notices
sent by telecopier shall be deemed to have been given upon confirmation by
telecopy answerback (provided that the sending of any such notice is followed
promptly by the mailing of the original of such notice). Notices mailed by
registered or certified mail shall be deemed to have been given upon the
expiration of five (5) Business Days after such notice has been deposited in the
mail.

                  (h) GOVERNING LAW; CONSENT TO JURISDICTION. This Agreement
shall be governed by and construed in accordance with the law of the State of
Delaware without regard to any applicable principles of conflicts of law. Each
party agrees that, in connection with any legal suit or proceeding arising with
respect to this Agreement, it shall submit to the non-exclusive jurisdiction of
the United States District Court for the Southern District of New York or the
applicable New York state court located in New York County and agrees to venue
in such courts.

                  (i) COUNTERPARTS. This Agreement may be executed in any number
of counterparts, each of which shall be deemed an original but all of which
shall constitute one and the same instrument.

                           [SIGNATURE PAGES TO FOLLOW]

                                       21
<PAGE>

                  IN WITNESS WHEREOF, the parties hereto have executed this
Agreement as of the day and year first written above.

                                    MOBILE SATELLITE VENTURES GP INC.

                                    By:     /S/ RANDY SEGAL
                                            ------------------------------------
                                            Name:  Randy Segal
                                            Title:  Secretary

                                    MOTIENT VENTURES HOLDING INC.

                                    By:     /S/ CHRIS DOWNIE
                                            ------------------------------------
                                            Name:  Chris Downie
                                            Title:  EVP & COO

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       22
<PAGE>

                                    TMI COMMUNICATIONS DELAWARE, LIMITED
                                    PARTNERSHIP

                                    By:     3924505 Canada, Inc., its General
                                            Partner

                                    By:     /S/ RORY MCCORMICK
                                            ------------------------------------
                                            Name:  Rory McCormick
                                            Title:  President

                                    MSV INVESTORS, LLC

                                    By:     MSV Investors Holdings, Inc., its
                                            Managing Member

                                    By:     /S/ JEFFREY A. LEDDY
                                            ------------------------------------
                                            Name:  Jeffrey A. Leddy
                                            Title:  CEO

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       23
<PAGE>

                                    TELCOM SATELLITE VENTURES II, INC.

                                    By:     /S/ HAL B. PERKINS
                                            ------------------------------------
                                            Name:  Hal B. Perkins
                                            Title: Vice President and General
                                                   Counsel

                                    TELCOM SATELLITE VENTURES INC.

                                    By:     /S/ HAL B. PERKINS
                                            ------------------------------------
                                            Name:  Hal B. Perkins
                                            Title: Vice President and General
                                                   Counsel

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       24
<PAGE>

                                    SPECTRUM SPACE EQUITY INVESTORS IV-II, INC.

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

                                    SPECTRUM SPACE IV PARALLEL II, INC.

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

                                    SPECTRUM SPACE IV MANAGERS II, INC.

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

                    SPECTRUM SPACE EQUITY INVESTORS IV, INC.

                                       25
<PAGE>

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

                                    SPECTRUM SPACE IV PARALLEL, INC.

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       26
<PAGE>

                                    SPECTRUM SPACE IV MANAGERS, INC.

                                    By:     /S/ KEVIN J. MARONI
                                            ------------------------------------
                                            Name:  Kevin J. Maroni
                                            Title:  Authorized Signatory

                                    COLUMBIA SPACE (QP) II, INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

                                    COLUMBIA SPACE (AI) II, INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

                                    COLUMBIA SPACE PARTNERS II, INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       27
<PAGE>

                                    COLUMBIA SPACE (QP), INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

                                    COLUMBIA SPACE (AI), INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

                                    COLUMBIA SPACE PARTNERS, INC.

                                    By:     /S/ DONALD A. DOERING
                                            ------------------------------------
                                            Name:  Donald A. Doering
                                            Title:  Authorized Signatory

         [SIGNATURE PAGE - AMENDED AND RESTATED STOCKHOLDERS' AGREEMENT]

                                       28

Source: [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00074-of-00352.parquet"}, [{"source": "alea-institute/alea-institute/kl3m-data-edgar-agreements/train-00074-of-00352.parquet"}]]