EXHIBIT 10.56a

                             STOCKHOLDERS' AGREEMENT



     STOCKHOLDERS' AGREEMENT (this "Agreement"),  dated as of November 26, 2001,
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 ("Newco LP") and the Stockholders of General Partner listed
on Schedule I hereto (each individually, a "Stockholder," and collectively,  the
"Stockholders", and together with General Partner, the "Parties").

                                    RECITALS

     WHEREAS, each Stockholder is also either a limited partner of Newco LP or a
holder of notes convertible into limited  partnership  interests in Newco 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 Newco LP (on an  as-converted  basis in the case of the holders of
the Convertible Notes); and

     WHEREAS,  the  Stockholders  have formed General Partner for the purpose of
having it serve exclusively as General Partner of Newco LP pursuant to the terms
of that certain Limited  Partnership  Agreement of Mobile Satellite Ventures LP,
dated as of November 26, 2001, (the "Newco LP Agreement"); and

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

     WHEREAS,  General  Partner  and the  Stockholders  are  entering  into this
agreement pursuant to the terms of that certain Amended and Restated  Investment
Agreement,  dated  as of  October  12,  2001,  as  amended,  by  and  among  the
Stockholders  (and their  affiliates),  the LLC and certain other parties (as in
effect on the date  hereof,  and  without  giving  effect  to any  modification,
amendment,  supplement or restatement thereof or waiver thereunder, the "October
Investment Agreement");

     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 Newco LP Agreement or,
if not defined  therein,  in the October  Investment  Agreement,  as applicable.
Additionally,  terms  defined in this Section 1 shall,  for the purposes of this
Agreement, have the meanings herein specified.

     "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 the October Investment 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.

     "Excluded  Securities"  means any interests in the  Partnership  (i) issued
pursuant  to the  October  Investment  Agreement  or  any  of  the  transactions
contemplated  thereby,  (ii) issued in connection  with the  acquisition  of the
business of another entity, whether by the purchase of equity securities, assets
or  otherwise,  (iii)  issued as part of an  Initial  Public  Offering  or other
registered  underwritten public offering of the Partnership's  securities,  (iv)
issued under an employee  compensation plan approved by the General Partner, (v)
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, and (vi) issued
pursuant to Section 8.1(h)(vi) of this Agreement.

     "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.

     "Intervening  Entity" shall mean, 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, the Partnership
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.

     "Pledge Agreement" means that certain Pledge and Guarantee Agreement, dated
as of even date  herewith,  by and  among  TMI,  TMI Sub and the  other  parties
thereto, as amended, supplemented or revised from time to time.

     "Spectrum  Investor  Group"  means the  entities in Spectrum  Space  Equity
Investors  IV,  Inc.'s  Investor  Group as set forth in the  October  Investment
Agreement.

     "Telcom  Investor  Group" means the entities in Telcom  Satellite  Ventures
Inc.'s Investor Group as set forth in the October Investment Agreement.

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

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)  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 be composed as follows:

(i) Subject to clause (ii) below,  assuming the First Closing has occurred,  the
Board shall consist of twelve (12) directors as follows:

(1) Each of 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 director under this Agreement (each such Person,  an "Investor Group
Assignee")),  acting through its respective  Investor Group  Designee,  shall be
entitled to designate one (1) director.  For the avoidance of doubt, in no event
shall the Telcom  Investor Group,  the Spectrum  Investor Group and the Columbia
Investor Group, or any transferees therefrom, be entitled to designate more than
three (3) directors in the aggregate.

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

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

(4) The Note Investors shall be entitled to designate three (3) directors.

(ii) In the event that the Second  Closing has not  occurred on or prior to June
30, 2003,  then  beginning on July 1, 2003,  the Board shall consist of ten (10)
directors as follows:

(1) The Telcom  Investor  Group,  the Spectrum  Investor  Group and the Columbia
Investor Group (or an Investor Group Assignee), as a group, shall be entitled to
designate a total of one (1) director.

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

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

(4) The Note Investors shall be entitled to designate three (3) directors.

(iii) For so long as the  Spectrum  Investor  Group  continues to be entitled to
designate a director under this Agreement,  Spectrum Space Equity  Investors IV,
Inc., a wholly-owned  subsidiary of Spectrum Equity IV, L.P.,  shall be entitled
to designate  such  director,  and such director  shall be a  representative  of
Spectrum Equity Investors IV, L.P. Spectrum Equity Investors IV, L.P. shall be a
third-party  beneficiary of this  Agreement to the extent  necessary in order to
enforce its rights under this Section 2(b)(iii).

(iv) For so long as the  Columbia  Investor  Group  continues  to be entitled to
designate  a  director  under this  Agreement,  Columbia  Space  (QP),  Inc.,  a
wholly-owned subsidiary of Columbia Capital Equity Partners (QP), L.P., shall be
entitled to designate such director, and such director shall be a representative
of Columbia Capital Equity Partners (QP), L.P.  Columbia Capital Equity Partners
(QP),  L.P.  shall be a third-party  beneficiary of this Agreement to the extent
necessary in order to enforce its rights under this Section 2(b)(iv).

(v) For so long as the Note  Investors  continue  to be  entitled  to  designate
directors under this Agreement, MSV Investors LLC shall be entitled to designate
such  directors,  and such directors shall be  representatives  of MSV Investors
LLC.

(c) Resignation. Any director may resign at any time by giving written notice to
the President of General Partner (the "President").  Such resignation shall take
effect at the time  specified  in such notice or, if the time be not  specified,
upon receipt  thereof by the  President.  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.

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 President 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"), the President or a majority of
the Board shall from time to time determine.

(c) Notice of Meetings. The Secretary of General Partner (the "Secretary") shall
give written  notice to 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 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  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.

(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 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 otherwise expressly
required by this Agreement or the October 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:

(1) the Chairman;

(2) the President; or

(3) 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 Investor
Group  designee,  one Motient Sub designee,  one TMI Sub designee,  and one Note
Investor 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 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.

(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 travelling  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 Newco
LP in any other capacity and receiving compensation therefor.

(j)  Selection of Officers.  The initial  officers of General  Partner  shall be
those set forth in General Partner's organizational  resolutions and any changes
thereto 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  Newco 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 Newco LP required  by the Newco LP  Agreement,  the Board shall not
permit or cause General Partner or Newco LP to enter into  transactions with its
Limited  Partners or  Affiliates  of its Limited  Partners  except as  otherwise
permitted in the October Investment  Agreement;  provided that Newco LP shall be
permitted to enter into each of the other Ancillary Agreements.

Section 4. 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 Investors' designees, the
Motient Sub designees, the TMI Sub designees, and the Note Investor designees to
be elected to the Board, in accordance with the provisions hereof.

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 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 October 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 by Investors to
an Investor Group Assignee in accordance with Section 2(b)(i)(1).

Section 7. Transfer of Shares; Redemption.

(a) 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 Newco LP (on an as-converted basis
in the case of the holders of the  Convertible  Notes).  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 or Articles 3 and 7 of the October  Investment  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 or Convertible Notes, Transfer its Shares (or the same portion thereof
as the Limited Partnership Interests or Convertible Notes being transferred bear
to its total Limited Partnership Interests (on an as-converted basis in the case
of the holders of the Convertible Notes)) to the purchaser or assignee of any of
its Limited  Partnership  Interests  or  Convertible  Notes in  accordance  with
Section 8 of this  Agreement or the  applicable  provisions  of the  Convertible
Notes.  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)(1) 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.

(b)  Redemption;  Effect of Redemption and Transfer.  In the event that Newco LP
repays any of the principal  amount of Convertible  Notes,  in whole or in part,
General Partner shall purchase from each Note Investor whose  Convertible  Notes
are being repaid (in whole or in part), and each Note Investor whose Convertible
Notes are being  repaid (in whole or in part) shall sell to General  Partner,  a
number  of Shares  equal to the  product  of (I) the sum of the total  number of
Shares issued to such Note Investor by General Partner  (appropriately  adjusted
for stock splits, combinations,  stock dividends,  reorganizations and the like)
multiplied by (II) a fraction,  the numerator of which shall equal the amount of
principal of such Note Investor's  Convertible  Note so paid and the denominator
of which shall equal the original principal amount of such Convertible Note. The
consideration  for any such  purchase  shall be $0.01  per  Share,  and the Note
Investor  holding such Shares shall  deliver such Shares to General  Partner for
cancellation promptly following any such repayment.  Additionally,  in the event
that:

(i)  Newco LP  repays in cash a total of more  than  one-third  of the  original
aggregate principal amount of the Convertible Notes, the size of the Board shall
be reduced by one (1)  director,  the Note  Investors  shall only be entitled to
designate two (2) directors,  and the Note Investors  shall cause one (1) of the
directors designated by them to resign from the Board;

(ii)  Newco LP repays in cash a total of more than  two-thirds  of the  original
aggregate principal amount of the Convertible Notes, the size of the Board shall
be reduced by a total of two (2)  directors,  the Note  Investors  shall only be
entitled to designate  one (1) director and the Note  Investors  shall cause all
directors  designated by them,  other than such one (1) remaining  director,  to
resign from the Board; and

(iii) Newco LP repays in cash a total of more than ninety  percent  (90%) of the
original  aggregate  principal amount of the Convertible  Notes, the size of the
Board  shall be reduced by a total of three (3)  directors,  the Note  Investors
shall not be entitled to designate any directors,  the Note Investors  shall not
be entitled to designate  any  directors to serve on committees of the Board and
the Note Investor  shall cause all  directors  designated by them to resign from
the Board.

Section 8 Transfers, Admission of Limited Partners and Conversion.

Section 8.1 Additional Issuances of Interests.

(a) In order to raise capital for Newco LP operations or to acquire  assets,  to
redeem  or  retire  Newco LP debt,  or for any other  valid  Newco 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 Newco LP to cause Newco LP to
issue additional  interests in Newco LP to the Limited Partners or other Persons
and to admit  such  other  Persons to Newco 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
Newco LP.

(b) Subject to clause (h) below,  General  Partner shall not issue any interests
in Newco LP unless it first  delivers to each Limited  Partner and Note Investor
(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 Newco LP then intends to issue (the "Offered  Interests"),
all of the material  terms,  including  the price (cash or non-cash)  upon which
Newco 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.

(c) During the ten (10)  consecutive day period  commencing on the date Newco 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 Newco 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:

(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
Newco  LP has  issued  (the  "Issued  Interests"),  all of the  material  terms,
including the price (the "Issued  Interest  Price") at which Newco 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 Newco 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.

Section 8.2 Transfers.  Except as set forth in Sections 8.2(c) and (d) or in the
October  Investment  Agreement,  until September 30, 2002, no Limited Partner or
Note  Investor  shall be permitted  to transfer  any of its Limited  Partnership
Interests or  Convertible  Notes to any Person without the consent of a majority
in interest  (determined on an as-converted  basis) of the Limited  Partners and
Note Investors who are neither  transferors nor  transferees,  nor members of an
Investor Group which includes a transferee or  transferor.  After  September 30,
2002, no Limited Partner or Note Investor may assign or transfer all or any part
of its Limited Partnership  Interest or Convertible Notes to any Person,  except
in compliance with the following:

(a) Right of First  Refusal.  In the event  that after  September  30,  2002,  a
Limited Partner or Note Investor (a "Selling Party") proposes to transfer all or
a portion of its Limited Partnership  Interest or Convertible Notes 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 or Convertible  Notes  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 and Note Investor,
whereupon  each other Limited  Partner and Note Investor 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 or  Convertible  Note
based upon such Limited  Partner's or Note Investor's  portion of the Percentage
Interests  (determined on an  as-converted  basis with respect to holders of the
Convertible  Notes) held by all Limited  Partners and Note Investors  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 or Note Investor  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 and Note Investors such
interests  or  Convertible  Notes at the price and on the terms as  contained in
such  Transfer  Notice.  Each  Limited  Partner  or Note  Investor  desiring  to
participate  in such  purchase  shall  provide the Selling  Party and each other
Limited  Partner and Note Investor  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 or Note Investor  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 or Note  Investors  do not provide a
timely  Participation  Notice, the Unallocated Portion shall be allocated in pro
rata  proportion  to  the  Percentage  Interest  (after  giving  effect  to  the
conversion of the  Convertible  Notes) held by each of the Limited  Partners and
Note Investors who submits a Participation  Notice to the extent of such Limited
Partner's or Note  Investor's  indicated  willingness to acquire any Unallocated
Portion as provided in such Limited  Partners' or Note Investor's  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  or  Convertible  Notes that such  Limited  Partner  or Note  Investor
specifies in the Participation Notice. In the event that the Limited Partners or
Note  Investors are not willing to purchase all of the interests or  Convertible
Notes 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 or Convertible Notes the Limited Partners and Note Investors
are  willing  to  accept  is less  than  the  minimum  amount  of  interests  or
Convertible  Notes which the offeror is willing to purchase pursuant to the bona
fide offer described in the Transfer Notice,  then the Limited Partners and Note
Investors  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 and Note Investors  shall have accepted all or part of the interests or
Convertible  Notes offered  pursuant to the Transfer  Notice (and shall not have
been  deemed to have  rejected  the offer in its  entirety as  described  in the
immediately  preceding  sentence),  then the  Selling  Party  shall sell to such
Limited Partners and Note Investors such interests or Convertible  Notes as have
been accepted by such Limited  Partners and Note  Investors as specified in such
Limited Partner's or Note Investor's Participation Notice on the terms contained
in the  Transfer  Notice.  Any  interests or  Convertible  Notes not sold to the
Limited  Partners or Note  Investors  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  or  Convertible  Notes  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  or  Convertible  Notes 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 or any portion of
     the Convertible Notes 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 and Note Investors (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,  or, with respect to the Convertible
     Notes,  at a purchase  price per Unit  calculated  by dividing the purchase
     price of such offer  divided  by the number of Common  Units into which the
     portion  of  such  Convertible  Note  proposed  to be  transferred  is then
     convertible  (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 or portion of such Convertible Note, to include in the transfer to
     the third party transferee a portion of Limited Partnership Interests,  or,
     with  respect  to  transfers  of  Convertible  Notes,  a  number  of  Units
     determined in accordance with this Section 8.2(b).

          (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 or
     Convertible Note 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 or Convertible Note the price of
     which (based on the Tag Along Price of such Limited Partnership Interest or
     Convertible  Note) equals the total  original  price proposed to be paid by
     the  transferee for the Selling  Party's  Limited  Partnership  Interest or
     portion of a Convertible  Note  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  or
     portion of a  Convertible  Note 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 or Convertible  Note 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  or
     Convertible  Note 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 the sale
     of any Limited  Partnership  Interest or Convertible  Note offered by it if
     the  transferee  does not purchase all Limited  Partnership  Interests  and
     portions of Convertible  Notes 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 and portions of Convertible Notes 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.

(c) Subject to Sections 8.2(e),  (f) and (g), a Limited Partner or Note Investor
may at any time and from time to time (i)  transfer  all or part of such Limited
Partner's Limited Partnership  Interest or Note Investor's  Convertible Notes to
any of such Limited  Partner's or Note Investor's  Family Members  provided that
such Limited  Partner or Note Investor shall provide the other Partners and Note
Investors notice of the identity of such Family Member transferee, (ii) transfer
all or part of its  Limited  Partnership  Interest or  Convertible  Notes 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 or Note Investor, as the case may be, 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 or of such Note  Investor's
Convertible Notes to a Control Party of such Note Investor;  provided, that such
Limited  Partner  or Note  Investor  and  Control  Party  agree with Newco LP in
writing that such Control Party shall transfer such Limited Partnership Interest
or Convertible  Notes back to such Limited Partner or Note Investor  immediately
upon such Person  ceasing to be a Control Party of such Limited  Partner or Note
Investor.  A Limited  Partner or Note  Investor 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  or  Convertible  Notes,
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), a Class A Limited Partner
may at any  time  and  from  time to time  transfer  all or part of its  Limited
Partnership Interest to another Class A Limited Partner.

(d) Each of TMI Sub,  Motient  Sub and the Lead  Note  Investor  shall  have the
right,  subject to Sections 8.2(a), (e), (f), and (g), to assign or transfer its
interest in Newco LP to any Person owning 10% or more of the outstanding  common
stock of BCE Inc.,  Motient or Rare Medium Group,  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 Newco 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,  of the  date  even  herewith  between  BCE  Inc.  and  Newco LP (the
"Non-Interference  Agreement")  applicable  to BCE Inc.,  (ii) the  Stockholders
Agreement,  of the date even  herewith,  by and among  TMI,  Newco 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  or  Convertible  Notes,  no Limited
Partnership Interest or Convertible Note 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 or Note
Investor set forth in this  Agreement and the Newco LP Agreement,  (ii) pays any
reasonable  expenses of Newco 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 Newco LP's taxable year with  respect to all Limited  Partners,  in the
termination  of Newco 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 Newco LP
to be in violation of any applicable  state or federal  securities laws or (iii)
result in an interest in Newco LP being held by a Person whose  participation in
the ownership of Newco LP would be detrimental to Newco LP;  provided,  however,
that no  transfer  made  pursuant  to  Section  8.2(c)  hereof  shall be  deemed
detrimental to Newco 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 Newco LP
Agreement  with respect to the transfer or  assignment  of interests in Newco 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.

(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 Newco
LP Agreement.

(j) Except as set forth in the last  sentence  of this  paragraph,  (1) upon any
transfer of Class A Preferred Units and Limited Partnership Interests by a Class
A Limited Partner to Motient Sub, TMI Sub or any Affiliate of either of them, or
(2) if any Class A Preferred Units otherwise become held by Motient Sub, TMI Sub
or any Affiliate of either of them, except with the prior written consent of the
Class A Limited  Partners other than the  transferring  Class A Limited Partner,
none of Motient Sub, TMI Sub or any Affiliate of either of them, shall be deemed
to be a Class A  Limited  Partner  or  shall  be  entitled  to vote as a Class A
Limited  Partner  and the Class A  Preferred  Units so  acquired  or held  shall
automatically  convert into the number of Common Units which at the time of such
conversion equals the Percentage  Interest  represented by the Class A Preferred
Units so  acquired.  Notwithstanding  the  foregoing,  in the event  that any of
Motient Sub, TMI Sub, or any  Affiliates  of either of them pay a portion of the
Investor  Purchase  Price at the Second  Closing  pursuant to Section 2.3 of the
October  Investment  Agreement,  such  Units  purchased  by such  Persons at the
Closing  shall be Class A  Preferred  Units and shall  not be  converted,  or be
deemed to have been  converted,  into Common  Units by operation of this Section
8.2(j).

(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 or the aggregate  amount of
Convertible  Notes  owned  directly or  indirectly  by such  Intervening  Entity
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 or Convertible
Notes occurs without  compliance  with the  provisions of this  Agreement  then,
without  limiting the rights of Newco LP or the other Partners or Note Investors
at law or in equity,  all of the Limited Partners and Note Investors (other than
the Limited Partner which is so deemed to have transferred  Limited  Partnership
Interests or Note Investor deemed to have transferred  Convertible  Notes) shall
have the right to purchase  the Limited  Partnership  Interests  or  Convertible
Notes  so  deemed  transferred  as if  such  Limited  Partnership  Interests  or
Convertible  Notes 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,   Limited  Partnership   Interests  or
Convertible Notes 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 Newco LP shall not be admitted
to Newco  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 Newco LP  Agreement,  the October
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 Newco LP
incurred in  connection  with such  admission  (including,  without  limitation,
attorney's fees). Such assignee or transferee shall automatically be admitted to
Newco LP as a Limited Partner  following  satisfaction of the provisions of this
Section 8.3(a).

(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 Newco 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 Newco LP and shall not
have any rights of a Limited  Partner under the Delaware Act, this  Agreement or
the Newco LP Agreement.

(c) A transferor  of interests  shall remain a Limited  Partner of Newco 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 Newco LP interests  issued pursuant
to Section 8.1 shall be admitted to Newco LP as an  Additional  Limited  Partner
upon furnishing to Newco 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. Additionally, any Note Investor who converts its
Convertible Notes into Limited Partnership  Interests shall be admitted to Newco
LP as an  Additional  Limited  Partner  (to the extent  that such  holder is not
already  a  Limited  Partner)  on the  terms  and  conditions  set forth in such
Convertible Notes and this Agreement. Additionally, any Second Closing Investors
who  purchase  Limited  Partnership  Interests  at the Second  Closing  shall be
admitted  to  Newco  LP as an  Additional  Limited  Partner  on  the  terms  and
conditions set forth in the October Investment Agreement.

Section 8.5 Corporate Conversion; Drag-Along Rights.

(a) At any time prior to the Second  Closing,  upon the consent of Motient  Sub,
TMI Sub and  Class A  Limited  Partners  holding a  majority  of the  Percentage
Interests held by all Class A Limited Partners, and at any time after the Second
Closing, at the General Partner's  discretion,  Newco LP shall be converted into
corporate form ("Newco") 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  Newco  LP's  (or its
successor's)  securities,  the  outstanding  interests  in  Newco  LP  shall  be
converted into common stock of Newco 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  Newco  LP's  (or  its  successor's)  securities,  (i)  the
respective  outstanding interests of Newco LP shall be converted into securities
of Newco 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 Newco will contain such  provisions as may be  necessary,  to allow
Newco to mimic,  as closely as  practicable,  the governance and other operating
provisions  of  the  Newco  LP  Agreement,  including,  without  limitation,  an
agreement by all  shareholders  holding stock with special  voting,  economic or
other rights to convert such stock into common  stock  immediately  prior to the
initial  public  offering  of  Newco  securities  on a  basis  similar  to  that
contemplated  by the  second  sentence  of this  Section  8.5(a).  To the extent
permitted by applicable law (including without limitation, Section 17-219 of the
Delaware Act), the consents of Limited Partners,  required by the first sentence
of this Section 8.5(a) shall be the only consents of Limited Partners  necessary
for  Newco LP to  effect a  Corporate  Conversion  and no other  class  votes or
consents  of Limited  Partners  or the  General  Partner  shall be  required  in
connection therewith.

(b) At any time after the Second Closing, 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 Newco 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 Newco 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 Newco 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
based  solely  on the  respective  Percentage  Interests  held by  such  Limited
Partners,  (i) until the second  anniversary of the date of the Second  Closing,
the consent of the Limited Partners holding a majority of the Common Units shall
be required with respect to any Drag-Along Transaction in which the value of the
aggregate   consideration  to  be  paid  to  the  Investors  for  their  Limited
Partnership  Interests  is less  than an  amount  equal to twice the sum of such
Investors' aggregate Capital Contributions and (ii) after the second anniversary
date of the Second 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 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 Newco LP Agreement and the October Investment Agreement, 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 October Investment Agreement and the
Newco LP 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.

(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 Newco LP shall admit any new limited partner (other than upon the
conversion  of any  Convertible  Notes) 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 Newco LP held by such new limited
partner  (after giving effect to the  conversion of the  Convertible  Notes then
outstanding)),  which  director(s)  shall  be  designated  by such  new  limited
partner.  Additionally,  any Second Closing Investors who purchase Shares at the
Second Closing shall be added by General  Partner as a Party hereto on the terms
and conditions set forth in the October Investment Agreement.

(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) 758-6134
                  Attention:  President

                  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).

     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 laws 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.



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

                            GENERAL PARTNER:


                            MOBILE SATELLITE VENTURES GP INC.

                            By:   /s/Carson E. Agnew
                                  ------------------
                            Name: Carson E. Agnew
                            Title: President

                            STOCKHOLDERS:

                            MOTIENT VENTURES HOLDING INC.

                            By:  /s/David H. Engvall
                                 -------------------
                            Name: David H. Engvall
                            Title: Vice President, General Counsel and Secretary

                            TMI COMMUNICATIONS DELAWARE, LIMITED PARTNERSHIP

                            By: 3924505 CANADA INC.,
                            Its General Partner

                            By:   /s/Rory McCormick
                                  -----------------
                            Name: Rory McCormick
                            Title: President



                            INVESTORS:

                            EXISTING INVESTORS:
                            -------------------

                            TELCOM SATELLITE VENTURES INC.


                            By:  /s/Hal B. Perkins
                                 -----------------
                            Name:  Hal B. Perkins
                            Title: Vice President



<PAGE>


                            NOTE INVESTORS:
                            --------------


                            TELCOM SATELLITE VENTURES II INC.

                            By:  /s/Hal B. Perkins
                                 -----------------
                            Name:  Hal B. Perkins
                            Title: Vice President


                            EXISTING INVESTORS:
                            ------------------


                            COLUMBIA SPACE (QP), INC.


                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary

                            COLUMBIA SPACE (AI), INC.

                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary

                            COLUMBIA SPACE PARTNERS, INC.

                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary



<PAGE>


                            NOTE INVESTORS:
                            --------------

                            COLUMBIA SPACE (QP) II, INC.

                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary

                            COLUMBIA SPACE (AI) II, INC.

                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary

                            COLUMBIA SPACE PARTNERS II, INC.

                            By:  /s/Donald A. Doering
                                 --------------------
                            Name:  Donald A. Doering
                            Title: Secretary



                            EXISTING INVESTORS:
                            ------------------


                            SPECTRUM SPACE EQUITY
                            INVESTORS IV, INC.


                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO

                            SPECTRUM SPACE IV PARALLEL, INC.


                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO

                            SPECTRUM SPACE IV MANAGERS, INC.

                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO

                            NOTE INVESTORS:
                            --------------

                            SPECTRUM SPACE EQUITY INVESTORS IV-II, INC.

                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO

                            SPECTRUM SPACE IV PARALLEL II, INC.

                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO

                            SPECTRUM SPACE IV MANAGERS II, INC.


                            By:  /s/Kevin J. Maroni
                                 ------------------
                            Name:  Kevin J. Maroni
                            Title: Chairman and CEO


                            MSV INVESTORS, LLC

                            By: MSV INVESTORS HOLDINGS,
                            INC., Its Managing Member


                            By: /s/Robert Lewis
                               ----------------
                            Name:  Robert Lewis
                            Title: President









<PAGE>


                                   SCHEDULE I

<TABLE>
<CAPTION>


                                  STOCKHOLDERS

------------------------------ --------------------------------------------------- ------------------------------
            Name                                    Address                              Number of Shares
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

<S>                            <C>                                                 <C>
Motient Sub                    10802 Parkridge Boulevard                           838.780487
                               Reston, Virginia 20191-5416
                               Tel:  (703) 758-6130
                               Fax:  (703) 758-6134
                               Attention:  David H. Engvall, Vice President and
                               General Counsel,

                               with a copy to:
                               Hogan & Hartson L.L.P.
                               8300 Greensboro Drive
                               Suite 1100
                               McLean, Virginia  22102
                               Tel:  (703) 610-6123
                               Fax:  (703) 610-6200
                               Attention:  Richard K.A. Becker, Esq.
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Telcom Satellite Ventures      211 North Union Street                              72.0000
Inc.                           Suite 300
                               Alexandria, Virginia 22314
                               Attention:  Hal B. Perkins
                               Tel:    (703) 706-3800
                               Fax:    (703) 706-3801
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Telcom Satellite Ventures II   211 North Union Street                              12.926829
Inc.                           Suite 300
                               Alexandria, Virginia 22314
                               Attention:  Hal B. Perkins
                               Tel:    (703) 706-3800
                               Fax:    (703) 706-3801
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space (QP), Inc.      211 North Union Street                              34.504242
                               Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:    (703) 519-3000
                               Fax:    (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space (AI), Inc.      211 North Union Street                              1.906112
                               Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:    (703) 519-3000
                               Fax:   (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:    (617) 951-2233
                               Fax:   (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space Partners, Inc.  211 North Union Street                              27.589646
                               Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space (QP) II, Inc.   211 North Union Street                              6.943039
                               Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space (AI) II, Inc.   211 North Union Street                              0.383553
                               Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Columbia Space Partners II,    211 North Union Street                              5.600237
Inc.                           Suite 300
                               Alexandria, Virginia 22314
                               Attention:  James B. Fleming
                               Tel:  (703) 519-3000
                               Fax:  (703) 519-3904
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:  (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------
                               One International Place
Spectrum Space Equity          29th Floor                                          62.880000
Investors IV, Inc.             Boston, MA 82110
                               Attention:  Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233 Fax:  (888)
                               325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Spectrum Space IV Parallel,    One International Place                             .3712
Inc.                           29th Floor
                               Boston, MA 82110
                               Attention:  Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Spectrum Space IV Managers,    One International Place                             .748800
Inc.                           29th Floor
                               Boston, MA 82110
                               Attention: Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------
                               One International Place
Spectrum Space Equity          29th Floor                                          12.700610
Investors IV-II, Inc.          Boston, MA 82110
                               Attention:  Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601
                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233 Fax:  (888)
                               325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Spectrum Space IV Parallel     One International Place                             .074976
II, Inc.                       29th Floor
                               Boston, MA 82110
                               Attention:  Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------

Spectrum Space IV Managers     One International Place                             .151244
II, Inc.                       29th Floor
                               Boston, MA 82110
                               Attention: Kevin J. Maroni
                               Tel:    (617) 464-4600
                               Fax:   (617) 464-4601

                               with a copy to:
                               Edwards & Angell, LLP
                               101 Federal Street
                               Boston, MA 02100
                               Attention:  Stephen O. Meredith, Esq.
                               Tel:   (617) 951-2233
                               Fax:  (888) 325-9120
------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------
                                                                                   663.648151
TMI Sub                        1601 Telesat Court
                               Gloucester Court
                               Canada K1B 1B9
                               Attn:  Rory McCormick

                               with a copy to:
                               Salans Hertzfeld Heilbronn Christy & Viener
                               Rockefeller Center
                               620 Fifth Avenue
                               New York, NY  10020-2457
                               Attn:  Owen D. Kurtin, Esq.
                               Tel:  (212) 623-8374
                               Fax: (212) 632-5555

------------------------------ --------------------------------------------------- ------------------------------
------------------------------ --------------------------------------------------- ------------------------------
                               c/o Rare Medium Group, Inc.
MSV Investors LLC              28 West 23rd Street                                 775.609742
                               New York, New York 10010
                               Attention:  General Counsel
                               Tel:    (646) 638-9600
                               Fax:    (646) 638-9716

                               with a copy to:

                               Skadden, Arps, Slate, Meagher & Flom LLP
                               Four Times Square
                               New York, New York 10036
                               Attn:  Gregory A. Fernicola, Esq.
                               Tel:   (212) 735-3000
                               Fax:   (212) 735-2000

------------------------------ --------------------------------------------------- ------------------------------



</TABLE>