EXHIBIT 10.1

                               MOTIENT CORPORATION

               AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT

         This AMENDED AND RESTATED REGISTRATION RIGHTS AGREEMENT (this
"Agreement") is effective as of October 27, 2005 and amends and restates in is
entirety the Registration Rights Agreement dated April 15, 2005 (the "Prior
Agreement") by and among Motient Corporation, a Delaware corporation, (the
"Company") and each purchaser of the Company's Series A Preferred (each such
purchaser, individually, a "Purchaser" and, collectively, the "Purchasers") set
forth on Schedule 1 to the Prior Agreement.

         WHEREAS, the Prior Agreement was entered into by the Company and the
Purchasers in connection with the purchase by the Purchasers of shares (the
"Series A Shares") of the Company's Series A Cumulative Convertible Preferred
Stock, $0.01 par value per share (the "Series A Preferred Stock") and was
binding on all assignees and transferees of the Series A Shares who agreed to be
bound by the terms thereof;

         WHEREAS, on the date hereof the Company consummated an exchange offer
(the "Exchange Offer") pursuant to which certain holders of Series A Shares
exchanged their Series A Shares for shares (the "Series B Shares" and, together
with the Series A Shares, the "Shares") of Series B Cumulative Convertible
Preferred Stock, $0.01 par value per share (the "Series B Preferred Stock" and,
together with the Series A Preferred Stock, the "Preferred Stock"); and

         WHEREAS, the Prior Agreement could be amended by obtaining the written
consent of the Company and the holders of a majority of the then outstanding
Registrable Shares (as defined in the Prior Agreement), and the holders of
Series A Shares who exchanged their Series A Shares for Series B Shares in the
Exchange Offer constituted the holders of a majority of the then outstanding
Registrable Securities, and pursuant to the terms of the Exchange Offer such
holders consented to the amendments to the Prior Agreement set forth in this
Agreement.

         NOW, THEREFORE, in consideration of the premises and mutual covenants
contained herein, the parties hereto hereby agree as follows:

         1. DEFINITIONS. The following terms shall have the meanings provided
therefor below or elsewhere in this Agreement as described below:

         "Affiliates" means any Person that, directly or indirectly, through one
or more intermediaries, controls, is controlled by, or is under common control
with, a Person, as such terms are used and construed under Rule 144, and in all
cases including, without limitation, any Person that serves as a general partner
and/or investment adviser or in a similar capacity of such a Person.

         "Board" means the Board of Directors of the Company.

         "Business Day" means any day except Saturday, Sunday and any day which
shall be a federal legal holiday or a day on which banking institutions in the
State of New York are authorized or required by law or other governmental action
to close.

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         "Certificates of Designations" means the Series A Certificate of
Designations and the Series B Certificate of Designations.

         "Closing Date" has the meaning set forth in the Securities Purchase
Agreement.

         "Common Stock" means the Company's common stock, par value $0.01 per
share (including any securities into which or for which such shares may be
exchanged for, or converted into, pursuant to any stock dividend, stock split,
stock combination, recapitalization, reclassification, reorganization or other
similar event).

         "Conversion Shares" means the Series A Conversion Shares and the Series
B Conversion Shares.

         "Dividend Shares" means the Series A Dividend Shares and the Series B
Dividend Shares.

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

         "Investors" means the Series A Investors and/or the Series B Investors.

         "Mandatory S-1 Registration Statement" means the Mandatory Series A S-1
Registration Statement and/or the Mandatory Series B S-1 Registration Statement.

         "Person" (whether or not capitalized) means an individual, partnership,
limited liability company, corporation, association, trust, joint venture,
unincorporated organization, and any government, governmental department or
agency or political subdivision thereof.

         "Prospectus" means the prospectus included in any Registration
Statement (including, without limitation, a prospectus that includes any
information previously omitted from a prospectus filed as part of an effective
Registration Statement in reliance upon Rule 430A promulgated under the
Securities Act), as amended or supplemented by any prospectus supplement, with
respect to the terms of the offering of any portion of the Registrable Shares
covered by such Registration Statement, and all other amendments and supplements
to the Prospectus, including post-effective amendments, and all material
incorporated by reference in such Prospectus.

         "Registrable Shares" means the Series A Registrable Shares and the
Series B Registrable Shares.

         "Registration Statement" means the Mandatory Series A S-1 Registration
Statement, the Mandatory Series B S-1 Registration Statement, any Demand
Registration on Form S-3, and any additional registration statements
contemplated by this Agreement, including (in each case) the Prospectus,
amendments and supplements to such registration statement or Prospectus,


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including pre- and post-effective amendments, all exhibits thereto, and all
material incorporated by reference in such registration statement or Prospectus.

         "Rule 144" means Rule 144 promulgated under the Securities Act and any
successor or substitute rule, law or provision.

         "SEC" means the Securities and Exchange Commission.

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

         "Securities Purchase Agreement" means the Securities Purchase Agreement
dated April 15, 2005 by and among the Company and the Purchasers.

         "Series A Certificate of Designations" means the Certificate of
Designations of the Series A Cumulative Convertible Preferred Stock filed with
the Secretary of State of the State of Delaware on April 15, 2005 as corrected
by the Certificate of Correction Filed to Correct a Certain Error in the
Certificate of Designations of the Series A Cumulative Convertible Preferred
Stock filed with the Secretary of State of the State of Delaware on July 29,
2005.

         "Series B Certificate of Designations" means the Certificate of
Designations of the Series B Cumulative Convertible Preferred Stock filed with
the Secretary of State of the State of Delaware on or prior to the date hereof.

         "Series A Conversion Shares" means the shares of Common Stock issuable
upon conversion of the Series A Preferred Stock as set forth in the Series A
Certificate of Designations.

         "Series B Conversion Shares" means the shares of Common Stock issuable
upon conversion of the Series B Preferred Stock as set forth in the Series B
Certificate of Designations.

         "Series A Dividend Shares" means the 2,000,000 shares of Common Stock
issuable as a dividend on the Series A Shares.

         "Series B Dividend Shares" means the 2,000,000 shares of Common Stock
issuable as a dividend on the Series B Shares.

         "Series A Investors" means the holders of Series A Shares or Series A
Registrable Shares.

         "Series B Investors" means the holders of Series B Shares or Series B
Registrable Shares.

         "Series A Registrable Shares" means, at the relevant time of reference
thereto, the Series A Conversion Shares, the Warrant Shares, the Series A
Dividend Shares (including any shares of capital stock that may be issued in


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respect thereof pursuant to a stock split, stock dividend, recombination,
reclassification or the like) and any shares of Common Stock issued as a
dividend on the Series A Shares in excess of the Series A Dividend Shares,
provided, however, that the term "Series A Registrable Shares" shall not include
any of the Series A Conversion Shares, Series A Dividend Shares or Warrant
Shares that are actually sold pursuant to a registration statement that has been
declared effective under the Securities Act by the SEC.

         "Series B Registrable Shares" means, at the relevant time of reference
thereto, the Series B Conversion Shares, the Series B Warrant Shares, the
Dividend Shares (including any shares of capital stock that may be issued in
respect thereof pursuant to a stock split, stock dividend, recombination,
reclassification or the like) and any shares of Common Stock issued as a
dividend on the Series B Shares in excess of the Series B Dividend Shares,
provided, however, that the term "Series B Registrable Shares" shall not include
any of the Series B Conversion Shares, Series B Dividend Shares or Warrant
Shares that are actually sold pursuant to a registration statement that has been
declared effective under the Securities Act by the SEC.

         "Warrants" means the warrants to purchase Common Stock, dated April 15,
2005, issued by the Company to the Purchasers pursuant to the Securities
Purchase Agreement.

         "Warrant Shares" means the shares of Common Stock issued or issuable
upon the exercise of the Warrants.

         2.       MANDATORY FORM S-1 REGISTRATION.
                  --------------------------------

                  (a)(i) On June 24, 2005 the Company filed with the SEC a
Registration Statement on Form S-1 for the purpose of registering under the
Securities Act all of the Series A Registrable Shares for resale by, and for the
account of, each Purchaser as an initial selling stockholder thereunder (the
"Mandatory Series A S-1 Registration Statement"). The Mandatory Series A S-1
Registration Statement shall permit the Series A Investors to offer and sell, on
a delayed or continuous basis pursuant to Rule 415 under the Securities Act, any
or all of the Series A Registrable Shares. The Company agrees to use its best
efforts to cause the Mandatory Series A S-1 Registration Statement to be
declared effective as soon as possible but in no event later than the date that
is (i) one hundred fifteen (115) days following the Closing Date in the event
the Mandatory Series A S-1 Registration Statement is not reviewed by the SEC or
(ii) one hundred forty-five (145) days following the Closing Date in the event
the Mandatory Series A S-1 Registration Statement is reviewed by the SEC (the
"Mandatory Effective Date") (including filing with the SEC, within three (3)
Business Days of the date that the Company is notified (orally or in writing,
whichever is earlier) by the SEC that the Mandatory Series A S-1 Registration
Statement will not be "reviewed" or will not be subject to further review, a
request for acceleration of effectiveness in accordance with Rule 461
promulgated under the Securities Act (an "Acceleration Request"), which request
shall request an effective date that is within three (3) Business Days of the
date of such request). The Company shall notify each Investor in writing
promptly (and in any event within one (1) Business Day) after the Company's
submission of an Acceleration Request to the SEC relating to the Mandatory
Series A S-1 Registration Statement. The Company shall be required to keep the
Mandatory Series A S-1 Registration Statement continuously effective (including
through the filing of any required post-effective amendments) until the earlier


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to occur of (i) the date after which all of the Series A Registrable Shares
registered thereunder shall have been sold and (ii) the second (2nd) anniversary
of the later to occur of (a) the Closing Date and (b) the date on which each
Warrant has been exercised in full and after which by the terms of such Warrant
there are no additional Warrant Shares as to which the Warrant may become
exercisable; provided, that in either case such date shall be extended by the
amount of time of any Suspension Period (as defined below). Thereafter, the
Company shall be entitled to withdraw the Mandatory Series A S-1 Registration
Statement and, upon such withdrawal, the Series A Investors shall have no
further right to offer or sell any of the Series A Registrable Shares pursuant
to the Mandatory Series A S-1 Registration Statement (or any prospectus relating
thereto).

                  (ii) As promptly as possible after the date hereof, the
Company shall prepare and file with the SEC a Registration Statement on Form S-1
for the purpose of registering under the Securities Act all of the Series B
Registrable Shares for resale by, and for the account of, each Series B Investor
as an initial selling stockholder thereunder (the "Mandatory Series B S-1
Registration Statement"). The Mandatory Series B S-1 Registration Statement
shall permit the Series B Investors to offer and sell, on a delayed or
continuous basis pursuant to Rule 415 under the Securities Act, any or all of
the Series B Registrable Shares. The Company agrees to use its best efforts to
cause the Mandatory Series B S-1 Registration Statement to be declared effective
as soon as possible following the date it is filed with the SEC. The Company
shall notify each Series B Investor in writing promptly (and in any event within
one (1) Business Day) after the Company's submission of an Acceleration Request
to the SEC relating to the Mandatory Series B S-1 Registration Statement. The
Company shall be required to keep the Mandatory Series B S-1 Registration
Statement continuously effective (including through the filing of any required
post-effective amendments) until the earlier to occur of (i) the date after
which all of the Series B Registrable Shares registered thereunder shall have
been sold and (ii) the second (2nd) anniversary of the later to occur of (a) the
Closing Date and (b) the date on which each Warrant has been exercised in full
and after which by the terms of such Warrant there are no additional Warrant
Shares as to which the Warrant may become exercisable; provided, that in either
case such date shall be extended by the amount of time of any Suspension Period
(as defined below). Thereafter, the Company shall be entitled to withdraw the
Mandatory Series B S-1 Registration Statement and, upon such withdrawal, the
Series B Investors shall have no further right to offer or sell any of the
Series B Registrable Shares pursuant to the Mandatory Series B S-1 Registration
Statement (or any prospectus relating thereto).

                  (b) Notwithstanding anything in this Section 2 to the
contrary, if the Company shall furnish to the Series A Investors and/or the
Series B Investors, as applicable, a certificate signed by the President, Chief
Executive Officer or Chief Operating Officer of the Company stating that the
Board has made the good faith determination (i) that the continued use by the
Series A Investors of the Mandatory Series A S-1 Registration Statement and/or
the continued use by the Series B Investors of the Mandatory Series B S-1
Registration Statement, as applicable, for purposes of effecting offers or sales
of Registrable Shares pursuant hereto would require, under the Securities Act
and the rules and regulations promulgated thereunder, premature disclosure in
the applicable Mandatory S-1 Registration Statement (or the Prospectus relating
thereto) of material, nonpublic information concerning the Company, its business
or prospects or any proposed material transaction involving the Company, (ii)
that such premature disclosure would be materially adverse to the Company, its


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business or prospects or any such proposed material transaction or would not be
in the best interests of the Company and (iii) that it is therefore essential to
suspend the use by the Series A Investors or the Series B Investors, as
applicable, of such Mandatory S-1 Registration Statement (and the Prospectus
relating thereto), then the right of the applicable Investors to use such
Mandatory S-1 Registration Statement (and the Prospectus relating thereto) for
purposes of effecting offers or sales of Registrable Shares pursuant thereto
shall be suspended for a period (the "Suspension Period") not greater than
fifteen (15) consecutive Business Days during any consecutive twelve (12) month
period. During the Suspension Period, the Investors shall not offer or sell any
Registrable Shares pursuant to or in reliance upon the applicable Mandatory S-1
Registration Statement (or the Prospectus relating thereto). The Company agrees
that, as promptly as possible, but in no event later than one (1) Business Day,
after the consummation, abandonment or public disclosure of the event or
transaction that caused the Company to suspend the use of a Mandatory S-1
Registration Statement (and the Prospectus relating thereto) pursuant to this
Section 2(b), the Company will as promptly as possible lift any suspension,
provide the impacted Investors with revised Prospectuses, if required, and will
notify the impacted Investors of their ability to effect offers or sales of
Registrable Shares pursuant to or in reliance upon such Mandatory S-1
Registration Statement.

                  (c) It shall be a condition precedent to the obligations of
the Company to register Registrable Shares for the account of an Investor
pursuant to this Section 2 that such Investor furnish to the Company such
information regarding itself, the Registrable Shares held by it, and the method
of disposition of such Registrable Shares as shall be required by the Securities
Act to effect the registration of such Investor's Registrable Shares.

                  (d) Notwithstanding anything in this Agreement to the
contrary, the Investors' sole remedy for the failure of the Company to file the
Mandatory Series B S-1 Registration Statement as promptly as possible after the
date hereof, or for the failure of the Company to make effective the Mandatory
Series A S-1 Registration Statement on or prior to the Mandatory Effective Date,
shall be the vesting of the Warrants as provided for therein.

         2A.      MANDATORY S-3 REGISTRATION RIGHTS.
                  ----------------------------------

                  (a) If, at any time any Registrable Shares are not able to be
resold pursuant to an effective Registration Statement, (i) Form S-3 (or other
equivalent form) is then available for the registration of such Registrable
Shares and (ii) the Company shall receive from any Investor (including for this
purpose its Affiliates) who holds (or who together hold) at least twenty-five
percent (25%) of the then outstanding Registrable Shares a written request or
requests (a "Demand Notice") that the Company effect a registration on Form S-3
(a "Demand Registration"), or any successor or substitute form, with respect to
all or a part of the Registrable Shares owned by such Investor(s), then the
Company will promptly give written notice of the proposed registration and the
Investor's or Investors' request therefor to all other Investors, and use best
efforts to effect such registration, as soon as practicable and in any event
within thirty (30) days, of all or such portion of such Investors' Registrable
Shares as are specified in such request, together with all or such portion of
the Registrable Shares of any other Investor or Investors joining in such
request as are specified in a written request given by such other Investor or


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Investors within ten (10) Business Days after receipt of such written notice
from the Company; provided, however, that the Company may temporarily suspended
the use of such registration statement for the same reasons and on the same
terms as described in Section 2(b) above. The Company shall not be required to
effect more than three (3) registrations pursuant to this Section 2A(a) during
any consecutive twelve (12) month period.

                  (b) It shall be a condition precedent to the obligations of
the Company to register Registrable Shares for the account of an Investor
pursuant to this Section 2A that such Investor furnish to the Company such
information regarding itself, the Registrable Shares held by it, and the method
of disposition of such Registrable Shares as shall be required by the Securities
Act to effect the registration of such Investor's Registrable Shares.

         3.       "PIGGYBACK" REGISTRATION.
                  -------------------------

                  (a) If at any time any Registrable Shares are not able to be
resold pursuant to an effective Registration Statement, and the Company proposes
to register any of its Common Stock under the Securities Act, whether as a
result of an offering for its own account or the account of others (but
excluding any registrations to be effected on Forms S-4 or S-8 or other
applicable successor Forms), the Company shall, each such time, give to the
Investors twenty (20) days' prior written notice of its intent to do so, and
such notice shall describe the proposed registration and shall offer such
Investors the opportunity to register such number of Registrable Shares as each
such Investor may request. Upon the written request of any Investor given to the
Company within fifteen (15) days after the receipt of any such notice by the
Company, the Company shall include in such Registration Statement all or part of
the Registrable Shares of such Investor, to the extent requested to be
registered.

                  (b) If a registration pursuant to Section 3 hereof involves an
underwritten offering and the managing underwriter shall advise the Company in
writing that, in its opinion, the number of shares of Common Stock requested by
the Investors to be included in such registration is likely to affect materially
and adversely the success of the offering or the price that would be received
for any shares of Common Stock offered in such offering, then, notwithstanding
anything in this Section 3 to the contrary, the Company shall only be required
to include in such registration, to the extent of the number of shares of Common
Stock which the Company is so advised can be sold in such offering, (i) first,
the number of shares of Common Stock requested to be included in such
registration for the account of any stockholders of the Company (including the
Investors), pro rata among such stockholders on the basis of the number of
shares of Common Stock that each of them has requested to be included in such
registration, and (ii) second, any shares of Common Stock proposed to be
included in such registration for the account of the Company.

                  (c) In connection with any offering involving an underwriting
of shares, the Company shall not be required under this Section 3 or otherwise
to include the Registrable Shares of any Investor therein unless such Investor
accepts and agrees to the terms of the underwriting, which shall be reasonable
and customary, as agreed upon between the Company and the underwriters selected
by the Company.

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                  (d) It shall be a condition precedent to the obligations of
the Company to register Registrable Shares for the account of an Investor
pursuant to this Section 3 that such Investor furnish to the Company such
information regarding itself, the Registrable Shares held by it, and the method
of disposition of such Registrable Shares as shall be required by the Securities
Act to effect the registration of such Investor's Registrable Shares.

         4.       OBLIGATIONS OF THE COMPANY. In connection with the Company's
registration obligations hereunder, the Company shall, as expeditiously as
practicable:

                  (a) furnish to each Investor copies of all documents filed
with the SEC prior to their being filed with the SEC, (ii) use commercially
reasonable efforts to cause its officers and directors, counsel and certified
public accountants to respond to such inquiries as shall be necessary, in the
reasonable opinion of such Investor, to conduct a reasonable investigation
within the meaning of the Securities Act, and (iii) notify the Investors of any
stop order issued or threatened by the SEC and use best efforts to prevent the
entry of such stop order or to remove it if entered.

                  (b) prepare and file with the SEC such amendments and
supplements, including post-effective amendments, to each Registration Statement
and the Prospectus used in connection therewith as may be necessary to comply
with the Securities Act and to keep the Registration Statement continuously
effective as required herein, and prepare and file with the SEC such additional
Registration Statements as necessary to register for resale under the Securities
Act all of the Registrable Shares (including naming any permitted transferees of
Registrable Shares as selling stockholders in such Registration Statement); (ii)
cause any related Prospectus to be amended or supplemented by any required
Prospectus supplement, and as so supplemented or amended to be filed pursuant to
Rule 424; (iii) respond as promptly as possible to any comments received from
the SEC with respect to each Registration Statement or any amendment thereto and
as promptly as possible provide the Investors true and complete copies of all
correspondence from and to the SEC relating to the Registration Statement (other
than correspondence containing material nonpublic information); and (iv) comply
with the provisions of the Securities Act and the Exchange Act with respect to
the disposition of all Registrable Shares covered by such Registration Statement
as so amended or in such Prospectus as so supplemented.

                  (c) Notify the Investors and Investors' counsel as promptly as
possible: (i) when the SEC notifies the Company whether there will be a "review"
of a Registration Statement and whenever the SEC comments in writing on such
Registration Statement and (ii) when a Registration Statement, or any
post-effective amendment or supplement thereto, has become effective, and after
the effectiveness thereof: (A) of any request by the SEC or any other federal or
state governmental authority for amendments or supplements to the Registration
Statement or Prospectus or for additional information; (B) of the issuance by
the SEC or any state securities commission of any stop order suspending the
effectiveness of the Registration Statement covering any or all of the
Registrable Shares or the initiation of any proceedings for that purpose; and
(C) of the receipt by the Company of any notification with respect to the
suspension of the qualification or exemption from qualification of any of the
Registrable Shares for sale in any jurisdiction, or the initiation or
threatening of any proceeding for such purpose. Without limitation of any


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remedies to which the Investors may be entitled under this Agreement, if any of
the events described in Section 4(c)(ii)(A), 4(c)(ii)(B), and 4(c)(ii)(C) occur,
the Company shall use best efforts to respond to and correct the event.

                  (d) Notify the Investors and their counsel as promptly as
possible of the happening of any event as a result of which the Prospectus
included in or relating to a Registration Statement contains an untrue statement
of a material fact or omits any fact necessary to make the statements therein
not misleading; and, thereafter, the Company will as promptly as possible
prepare (and, when completed, give notice to each Investor) a supplement or
amendment to such Prospectus so that, as thereafter delivered to the purchasers
of such Registrable Shares, such Prospectus will not contain an untrue statement
of a material fact or omit to state any fact necessary to make the statements
therein not misleading; provided that upon such notification by the Company, the
Investors will not offer or sell Registrable Shares pursuant to such Prospectus
until the Company has notified the Investors that it has prepared a supplement
or amendment to such Prospectus and delivered copies of such supplement or
amendment to the Investors (it being understood and agreed by the Company that
the foregoing proviso shall in no way diminish or otherwise impair the Company's
obligation to as promptly as possible prepare a Prospectus amendment or
supplement as above provided in this Section 4(d) and deliver copies of same as
above provided in Section 4(h) hereof), and it being further understood that, in
the case of the Mandatory S-1 Registration Statement, any such period during
which the Investors are restricted from offering or selling Registrable Shares
shall constitute a Suspension Period.

                  (e) Upon the occurrence of any event described in Section 4(d)
hereof, as promptly as possible, prepare a supplement or amendment, including a
post-effective amendment, to the Registration Statement or a supplement to the
related Prospectus or any document incorporated or deemed to be incorporated
therein by reference, and file any other required document so that, as
thereafter delivered, neither the Registration Statement nor such Prospectus
will contain an untrue statement of a material fact or omit to state a material
fact required to be stated therein or necessary to make the statements therein,
in light of the circumstances under which they are made, not misleading.

                  (f) Use best efforts to avoid the issuance of or, if issued,
obtain the withdrawal of, (i) any order suspending the effectiveness of any
Registration Statement or (ii) any suspension of the qualification (or exemption
from qualification) of any of the Registrable Shares for sale in any
jurisdiction, as promptly as possible (it being understood that, in the case of
a Mandatory S-1 Registration Statement, any period during which the
effectiveness of the Mandatory S-1 Registration Statement or the qualification
of any Registrable Shares is suspended shall constitute a Suspension Period).

                  (g) Furnish to the Investors and their counsel, without
charge, at least one conformed copy of each Registration Statement and each
amendment thereto, and all exhibits to the extent requested by such Investor or
their counsel (including those previously furnished or incorporated by
reference) as promptly as possible after the filing of such documents with the
SEC.

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                  (h) As promptly as possible furnish to each selling Investor,
without charge, such number of copies of a Prospectus, including a preliminary
Prospectus, in conformity with the requirements of the Securities Act, and such
other documents (including, without limitation, Prospectus amendments and
supplements) as each such selling Investor may reasonably request in order to
facilitate the disposition of the Registrable Shares covered by such Prospectus
and any amendment or supplement thereto. The Company hereby consents to the use
of such Prospectus and each amendment or supplement thereto by each of the
selling Investors in connection with the offering and sale of the Registrable
Shares covered by such Prospectus and any amendment or supplement thereto to the
extent permitted by federal and state securities laws and regulations.

                  (i) Use best efforts to register and qualify (or obtain an
exemption from such registration and qualification) the Registrable Shares under
such other securities or blue sky laws of the states of residence of each
Investor and such other jurisdictions as each Investor shall reasonably request,
to keep such registration or qualification (or exemption therefrom) effective
during the periods each Registration Statement is effective, and do any and all
other acts or things which may be reasonably necessary or advisable to enable
each Investor to consummate the public sale or other disposition of Registrable
Shares in such jurisdiction, provided that the Company shall not be required in
connection therewith or as a condition thereto to qualify to do business or to
file a general consent to service of process in any such states or jurisdictions
where it is not then qualified or subject to process.

                  (j) Cooperate with the Investors to facilitate the timely
preparation and delivery of certificates representing the Registrable Shares to
be delivered to a transferee pursuant to a Registration Statement, which
certificates shall be free, to the extent permitted by the Securities Purchase
Agreement and applicable law, of all restrictive legends, and to enable such
Registrable Shares to be in such denominations and registered in such names as
such Investors may request.

                  (k) Cooperate with any reasonable due diligence investigation
undertaken by the Investors, any managing underwriter participating in any
disposition pursuant to a Registration Statement, Investors' Counsel and any
attorney, accountant or other agent retained by Investors or any managing
underwriter, in connection with the sale of the Registrable Shares, including,
without limitation, making available any documents and information; provided,
however, that the Company will not deliver or make available to any Investor
material, nonpublic information unless such Investor specifically requests and
consents in advance in writing to receive such material, nonpublic information
and, if requested by the Company, such Investor agrees in writing to treat such
information as confidential.

                  (l) At the request of an Affiliate, the Company shall amend
any Registration Statement to include such Affiliate as a selling stockholder in
such Registration Statement.

                  (m) Comply with all applicable rules and regulations of the
SEC in all material respects.

                  (n) Prior to issuing any dividends on the shares of Series A


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Preferred Stock or Series B Preferred Stock payable in shares of Common Stock in
an amount in excess of the Dividend Shares, the Company will file a registration
statement registering the resale of such additional shares of Common Stock and
such registration statement shall be effective on the date such dividend is
declared by the Board.

         5.       EXPENSES OF REGISTRATION. The Company shall pay for all
expenses incurred in connection with a registration pursuant to this Agreement
and compliance with Section 4 of this Agreement, including without limitation
(i) all registration, filing and qualification fees and expenses (including
without limitation those related to filings with the SEC, The NASDAQ Stock
Market, or any national securities exchange upon which the Company's securities
are listed and in connection with applicable state securities or blue sky laws),
(ii) all printing expenses, (iii) all messenger, telephone and delivery expenses
incurred by the Company, (iv) all fees and disbursements of counsel for the
Company and Investors' counsel, and (v) all fees and expenses of all other
Persons retained by the Company in connection with the consummation of the
transactions contemplated by this Agreement.

         6.       DELAY OF REGISTRATION. Subject to Section 11(d) hereof, the
Investors and the Company (other than with respect to Section 4(d) hereof) shall
not take any action to restrain, enjoin or otherwise delay any registration as
the result of any controversy which might arise with respect to the
interpretation or implementation of this Agreement.

         7.       INDEMNIFICATION. In the event that any Registrable Shares of
the Investors are included in a Registration Statement pursuant to this
Agreement:

                  (a) To the fullest extent permitted by law, the Company will
indemnify and hold harmless each Investor and each officer, director, fiduciary,
agent, investment advisor, employee, member (or other equity holder), general
partner and limited partner (and affiliates thereof) of such Investor, each
broker, underwriter or other person acting on behalf of such Investor and each
person, if any, who controls such Investor within the meaning of the Securities
Act, against any losses, claims, damages or liabilities, joint or several, (the
"Losses") to which they may become subject under the Securities Act or
otherwise, insofar as such Losses (or actions in respect thereof) arise out of
or relate to any untrue or alleged untrue statement of any material fact
contained in the Registration Statement, or arise out of or relate to the
omission or alleged omission to state therein a material fact required to be
stated therein, or necessary to make the statements therein not misleading, or
any violation by the Company of the Securities Act or state securities or blue
sky laws applicable to the Company and leading to action or inaction required of
the Company in connection with such registration or qualification under such
Securities Act or state securities or blue sky laws; and, subject to the
provisions of Section 7(c) hereof, the Company will reimburse on demand such
Investor, such broker or other person acting on behalf of such Investor or such
officer, director, fiduciary, employee, member (or other equity holder), general
partner, limited partner, affiliate or controlling person for any legal or other
expenses reasonably incurred by any of them in connection with investigating or
defending any such Losses; provided, however, that the indemnity agreement
contained in this Section 7(a) shall not apply to amounts paid in settlement of
any such Losses if such settlement is effected without the consent of the
Company (which consent shall not be unreasonably withheld), nor shall the
Company be liable in any such case for any such Losses to the extent that it


                                       11
<PAGE>

solely arises out of or is based upon an untrue statement of any material fact
contained in the Registration Statement or omission to state therein a material
fact required to be stated therein or necessary to make the statements therein
not misleading, in each case to the extent that such untrue statement or alleged
untrue statement or omission or alleged omission was made in the Registration
Statement, in reliance upon and in conformity with written information furnished
by such Investor expressly for use in connection with such Registration
Statement.

                  (b) To the fullest extent permitted by law, each Investor,
severally (as to itself) and not jointly, will indemnify and hold harmless the
Company, each of its directors, each of its officers who have signed the
Registration Statement, each person, if any, who controls the Company within the
meaning of the Securities Act, and all other Investors against any Losses to
which the Company or any such director, officer or controlling person or other
Investor may become subject to, under the Securities Act or otherwise, insofar
as such Losses (or actions in respect thereto) solely arise out of or are based
upon any untrue statement of any material fact contained in the Registration
Statement, or solely arise out of or relate to the omission to state therein a
material fact required to be stated therein or necessary to make the statements
therein not misleading, in each case to the extent that such untrue statement or
alleged untrue statement or omission or alleged omission was made in the
Registration Statement in reliance upon and in conformity with written
information furnished by such Investor expressly for use in connection with such
Registration Statement; and, subject to the provisions of Section 7(d) hereof,
such Investor will reimburse on demand any legal or other expenses reasonably
incurred by the Company or any such director, officer, controlling person, or
other Investor in connection with investigating or defending any such Losses,
provided, however, that the maximum aggregate amount of liability of such
Investor under this Section 7 shall be limited to the proceeds (net of
underwriting discounts and commissions, if any) actually received by such
Investor from the sale of Registrable Shares covered by such Registration
Statement; and provided, further, however, that the indemnity agreement
contained in this Section 7(b) or Section 7(e) shall not apply to amounts paid
in settlement of any such Losses if such settlement is effected without the
consent of such Investor against which the request for indemnity is being made
(which consent shall not be unreasonably withheld).

                  (c) As promptly as possible after receipt by an indemnified
party under this Section 7 of notice of the threat, assertion or commencement of
any action, such indemnified party will, if a claim in respect thereof is to be
made against any indemnifying party under this Section 7, notify the
indemnifying party in writing of the commencement thereof and the indemnifying
party shall have the right to participate in and, to the extent the indemnifying
party desires, jointly with any other indemnifying party similarly noticed, to
assume at its expense the defense thereof with counsel mutually satisfactory to
the parties; provided, however, that, the failure to notify an indemnifying
party promptly of the threat, assertion or commencement of any such action shall
not relieve such indemnifying party of any liability to the indemnified party
under this Section 7 except (and only) to the extent that it shall be finally
determined by a court of competent jurisdiction (which determination is not
subject to appeal or further review) that such failure shall have proximately
and materially adversely prejudiced the indemnifying party.

                  (d) If any indemnified party shall have reasonably concluded
that there may be one or more legal defenses available to such indemnified party


                                       12
<PAGE>

which are different from or additional to those available to the indemnifying
party, or that such claim or litigation involves or could have an effect upon
matters beyond the scope of the indemnity agreement provided in this Section 7,
the indemnifying party shall not have the right to assume the defense of such
action on behalf of such indemnified party, and such indemnifying party shall
reimburse such indemnified party and any person controlling such indemnified
party for the fees and expenses of counsel retained by the indemnified party
which are reasonably related to the matters covered by the indemnity agreement
provided in this Section 7. Subject to the foregoing, an indemnified party shall
have the right to employ separate counsel in any such action and to participate
in the defense thereof but the fees and expenses of such counsel shall not be at
the expense of the Company.

                  (e) If the indemnification provided for in this Section 7 from
the indemnifying party is applicable by its terms but unavailable to an
indemnified party hereunder in respect of any Losses, then the indemnifying
party, in lieu of indemnifying such indemnified party, shall, subject to the
maximum aggregate liability of any Investor as set forth in Section 7(b),
contribute to the amount paid or payable by such indemnified party as a result
of such Losses or expenses in such proportion as is appropriate to reflect the
relative fault of the indemnifying party and indemnified party in connection
with the actions which resulted in such Losses or expenses, as well as any other
relevant equitable considerations. The relative faults of such indemnifying
party and indemnified party shall be determined by reference to, among other
things, whether any action in question, including any untrue or alleged untrue
statement of a material fact or omission or alleged omission to state a material
fact, has been made by, or relates to information supplied by, such indemnifying
party or indemnified party, and the parties' relative intent, knowledge, access
to information and opportunity to correct or prevent such action. The amount
paid or payable by a party as a result of the Losses and expenses referred to
above shall be deemed to include, subject to the limitations set forth in
Sections 7(a), 7(b), 7(c) and 7(d), any legal or other fees, charges or expenses
reasonably incurred by such party in connection with any investigation or
proceeding. No person guilty of fraudulent misrepresentation (within the meaning
of Section 11(f) of the Securities Act) shall be entitled to contribution from
any person. The parties hereto agree that it would not be just and equitable if
contribution pursuant to this Section 7(e) were determined by pro rata
allocation or by any other method of allocation which does not take account of
the equitable considerations referred to in the this paragraph.

                  (f) The indemnity and contribution agreements contained in
this Section are in addition to any liability that any indemnifying party may
have to any indemnified party.

         8.       REPORTS UNDER THE EXCHANGE ACT. With a view to making
available to the Investors the benefits of Rule 144 and any other rule or
regulation of the SEC that may at any time permit the Investors to sell the
Registrable Shares to the public without registration, the Company agrees to use
best efforts to: (i) make and keep public information available, as those terms
are understood and defined in Rule 144, (ii) file with the SEC in a timely
manner all reports and other documents required to be filed by an issuer of
securities registered under the Securities Act or the Exchange Act; (iii) as
long as any Investor owns any Conversion Shares, Warrant Shares or Dividend
Shares, to furnish in writing upon such Investor's request a written statement
by the Company that it has complied with the reporting requirements of Rule 144
and of the Securities Act and the Exchange Act, and to furnish to such Investor


                                       13
<PAGE>

a copy of the most recent annual and quarterly reports of the Company, and such
other reports and documents so filed by the Company as may be reasonably
requested in availing such Investor of any rule or regulation of the SEC
permitting the selling of any such Conversion Shares, Warrant Shares or Dividend
Shares without registration, and (iv) undertake any additional actions
reasonably necessary to maintain the availability of a Registration Statement,
including any successor or substitute forms, or the use of Rule 144.

         9.       TRANSFER OF REGISTRATION RIGHTS. Each Investor may assign or
transfer any or all of its rights under this Agreement to any Person, provided
such assignee or transferee agrees in writing to be bound by the provisions
hereof that apply to such assigning or transferring Investor. Upon any such, and
each successive, assignment or transfer to any permitted assignee or transferee
in accordance with the terms of this Section 9, such permitted assignee or
transferee shall be deemed to be an "Investor" for all purposes of this
Agreement.

         10.      ENTIRE AGREEMENT. This Agreement constitutes and contains the
entire agreement and understanding of the parties with respect to the subject
matter hereof, and it also supersedes any and all prior negotiations,
correspondence, agreements or understandings with respect to the subject matter
hereof.

         11.      MISCELLANEOUS.
                  --------------

                  (a) This Agreement, and any right, term or provision contained
herein, may not be amended, modified or terminated, and no right, term or
provision may be waived, except with the written consent of (i) the holders of a
majority of the then outstanding Registrable Shares and (ii) the Company;
provided that any amendment or modification that is materially and
disproportionately adverse to any particular Investor (as compared to all
Investors as a group) shall require the consent of such Investor.

                  (b) This Agreement shall be governed by and construed and
enforced in accordance with the laws of the State of New York. This Agreement
shall be binding upon the parties hereto and their respective heirs, personal
representatives, successors and permitted assigns and transferees, provided that
the terms and conditions of Section 9 hereof are satisfied. Notwithstanding
anything in this Agreement to the contrary, if at any time any Investor
(including any successors or assigned) shall cease to own any Registrable
Shares, all of such Investor's rights under this Agreement shall immediately
terminate.

                  (c) Any notices to be given pursuant to this Agreement shall
be in writing and shall be given by certified or registered mail, return receipt
request. Notices shall be deemed given when personally delivered or when mailed
to the addresses of the respective parties as set forth on Exhibit A with
respect to the Company and at the address reflected in the transfer records of
the Company with respect to the Investors, or to such changed address of which
any party may notify the others pursuant hereto, except that a notice of change
of address shall be deemed given when received. An electronic communication
("Electronic Notice") shall be deemed written notice for purposes of this
Section 11(c) if sent with return receipt requested to the electronic mail
address specified by the receiving party on Exhibit A with respect to the
Company or at the address reflected in the transfer records of the Company with


                                       14
<PAGE>

respect to the Investors. Electronic Notice shall be deemed received at the time
the party sending Electronic Notice receives verification of receipt by the
receiving party.

                  (d) The parties acknowledge and agree that in the event of any
breach of this Agreement, remedies at law will be inadequate, and each of the
parties hereto shall be entitled to specific performance of the obligations of
the other parties hereto and to such appropriate injunctive relief as may be
granted by a court of competent jurisdiction. All remedies, either under this
Agreement or by law or otherwise afforded to any of the parties, shall be
cumulative and not alternative.

                  (e) This Agreement may be executed in a number of
counterparts. All such counterparts together shall constitute one Agreement, and
shall be binding on all the parties hereto notwithstanding that all such parties
have not signed the same counterpart. The parties hereto confirm that any
facsimile copy of another party's executed counterpart of this Agreement (or its
signature page thereof) will be deemed to be an executed original thereof.

                  (f) Except as contemplated in Section 9 hereof, this Agreement
is intended solely for the benefit of the parties hereto and is not intended to
confer any benefits upon, or create any rights in favor of, any Person
(including, without limitation, any stockholder or debt holder of the Company)
other than the parties hereto.

                  (g) If any provision of this Agreement is invalid, illegal or
unenforceable, such provision shall be ineffective to the extent, but only to
the extent of, such invalidity, illegality or unenforceability, without
invalidating the remainder of such provision or the remaining provisions of this
Agreement, unless such a construction would be unreasonable.

                            [Signature Pages Follow]


                                       15
<PAGE>


         IN WITNESS WHEREOF, the parties hereto have executed this Amended and
Restated Registration Rights Agreement as of the date and year first above
written.

                                     MOTIENT CORPORATION

                                     By: /s/ Christopher Downie
                                         ---------------------------
                                         Christopher Downie,
                                         Executive Vice President and
                                         Chief Operating Officer









                [SIGNATURE PAGE TO REGISTRATION RIGHTS AGREEMENT]

<PAGE>


                                                                       Exhibit A
                                                                       ---------

All correspondence to the Company shall be addressed as follows:

                               Motient Corporation
                            300 Knightsbridge Parkway
                             Lincolnshire, IL 60069
                         Attention: Christopher Downie,
              Executive Vice President and Chief Operating Officer
                           Facsimile: (847) 478-4810
                            Chris.Downie@Motient.com.

with copies (which shall not constitute Notice) to:

                               Motient Corporation
                            300 Knightsbridge Parkway
                             Lincolnshire, IL 60069
                         Attention: Robert Macklin, Esq.
                            Facsimile: (847) 478-4810
                           Robert.Macklin@Motient.com

                                       and

                                Andrews Kurth LLP
                              450 Lexington Avenue
                               New York, NY 10017
                        Attention: Paul Silverstein, Esq.
                            Facsimile: (212) 850-2929
                          psilverstein@andrewskurth.com