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UNITED STATES
SECURITIES AND EXCHANGE COMMISSION

Washington, D.C. 20549

SCHEDULE 13D

Under the Securities Exchange Act of 1934
(Amendment No. 13 )*

Motient Corporation

(Name of Issuer)

Common Stock, par value $0.01 per share

(Title of Class of Securities)

619908304

(CUSIP Number)

Patrick H. Daugherty, Esq.
Highland Capital Management, L.P.
Two Galleria Tower
13455 Noel Road, Suite 800
Dallas, Texas 75240
(972) 628-4100

(Name, Address and Telephone Number of Person Authorized to
Receive Notices and Communications)

January 27, 2006

(Date of Event Which Requires Filing of this Statement)

If the filing person has previously filed a statement on Schedule 13G to report the acquisition that is the subject of this Schedule 13D, and is filing this schedule because of §§240.13d-1(e), 240.13d-1(f) or 240.13d-1(g), check the following box. o

Note: Schedules filed in paper format shall include a signed original and five copies of the schedule, including all exhibits. See §240.13d-7 for other parties to whom copies are to be sent.

* The remainder of this cover page shall be filled out for a reporting person’s initial filing on this form with respect to the subject class of securities, and for any subsequent amendment containing information which would alter disclosures provided in a prior cover page.

The information required on the remainder of this cover page shall not be deemed to be “filed” for the purpose of Section 18 of the Securities Exchange Act of 1934 (“Act”) or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however, see the Notes).

Persons who respond to the collection of information contained in this form are not required to respond unless the form displays a currently valid OMB control number.

CUSIP No. 619908304  Page 2  of  16 

1	NAMES OF REPORTING PERSONS: Prospect Street High Income Portfolio, Inc.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
	04-3028343
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Maryland
		7	SOLE VOTING POWER:
NUMBER OF			1,155,224
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			1,155,224
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	1,155,224
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	1.8%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO/IV

CUSIP No. 619908304  Page 3  of  16 

1	NAMES OF REPORTING PERSONS: Prospect Street Income Shares Inc.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
	36-2765811
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Maryland
		7	SOLE VOTING POWER:
NUMBER OF			111,940
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			111,940
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	111,940
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	0.2%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO/IV

CUSIP No. 619908304  Page 4  of  16 

1	NAMES OF REPORTING PERSONS: Highland Legacy Limited
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Cayman Islands
		7	SOLE VOTING POWER:
NUMBER OF			223,880
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			223,880
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	223,880
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	0.4%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	OO

CUSIP No. 619908304  Page 5  of  16 

1	NAMES OF REPORTING PERSONS: Highland Crusader Offshore Partners, L.P.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Bermuda
		7	SOLE VOTING POWER:
NUMBER OF			5,352,497
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			5,352,497
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	5,352,497
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	8.6%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	PN

CUSIP No. 619908304  Page 6  of  16 

1	NAMES OF REPORTING PERSONS: PAMCO Cayman, Limited
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Cayman Islands
		7	SOLE VOTING POWER:
NUMBER OF			223,880
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			223,880
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	223,880
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	0.4%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	OO

CUSIP No. 619908304  Page 7  of  16 

1	NAMES OF REPORTING PERSONS: Highland Equity Focus Fund, L.P.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
	46-0491961
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		7	SOLE VOTING POWER:
NUMBER OF			1,518,779
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			1,518,779
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	1,518,779
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	2.4%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	PN

CUSIP No. 619908304  Page 8  of  16 

1	NAMES OF REPORTING PERSONS: Highland Select Equity Fund, L.P.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		7	SOLE VOTING POWER:
NUMBER OF			119,283
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			119,283
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	119,283
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	0.2%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	PN

CUSIP No. 619908304  Page 9  of  16 

1	NAMES OF REPORTING PERSONS: Highland Capital Management Services, Inc.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		7	SOLE VOTING POWER:
NUMBER OF			182,748
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			182,748
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	182,748
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	0.3%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO

CUSIP No. 619908304  Page 10  of  16 

1	NAMES OF REPORTING PERSONS: Highland Capital Management, L.P.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
	75-2716725
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	AF/WC
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		7	SOLE VOTING POWER:
NUMBER OF			8,822,764
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			8,822,764
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	8,822,764
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	14.1%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	IA/PN

CUSIP No. 619908304  Page 11  of  16 

1	NAMES OF REPORTING PERSONS: Strand Advisors, Inc.
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
	95-4440863
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	AF
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	Delaware
		7	SOLE VOTING POWER:
NUMBER OF			8,822,764
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			8,822,764
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	8,822,764
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	14.1%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	CO

CUSIP No. 619908304  Page 12  of  16 

1	NAMES OF REPORTING PERSONS: James Dondero
	I.R.S. IDENTIFICATION NOS. OF ABOVE PERSONS (ENTITIES ONLY):
2	CHECK THE APPROPRIATE BOX IF A MEMBER OF A GROUP (SEE INSTRUCTIONS):
	(a)   þ
	(b)   o
3	SEC USE ONLY:
4	SOURCE OF FUNDS (SEE INSTRUCTIONS):
	AF/PF
5	CHECK IF DISCLOSURE OF LEGAL PROCEEDINGS IS REQUIRED PURSUANT TO ITEMS 2(d) OR 2(e):
	o
6	CITIZENSHIP OR PLACE OF ORGANIZATION:
	United States
		7	SOLE VOTING POWER:
NUMBER OF			9,024,326
SHARES		8	SHARED VOTING POWER:
BENEFICIALLY
OWNED BY			0
EACH		9	SOLE DISPOSITIVE POWER:
REPORTING
PERSON			9,024,326
WITH		10	SHARED DISPOSITIVE POWER:
			0
11	AGGREGATE AMOUNT BENEFICIALLY OWNED BY EACH REPORTING PERSON:
	9,024,326
12	CHECK IF THE AGGREGATE AMOUNT IN ROW (11) EXCLUDES CERTAIN SHARES (SEE INSTRUCTIONS):
	o
13	PERCENT OF CLASS REPRESENTED BY AMOUNT IN ROW (11):
	14.4%
14	TYPE OF REPORTING PERSON (SEE INSTRUCTIONS):
	IN

Page 13 of 16

     This Amendment No. 13 to Schedule 13D amends and supplements the Schedule 13D filed with the Securities and Exchange Commission (the “Commission”) on June 10, 2002, as amended by Amendment No. 1 to Schedule 13D filed with the Commission on October 20, 2003, Amendment No. 2 to Schedule 13D filed with the Commission on July 12, 2004, Amendment No. 3 to Schedule 13D filed with the Commission on November 16, 2004, Amendment No. 4 to Schedule 13D filed with the Commission on April 19, 2005, Amendment No. 5 to Schedule 13D filed with the Commission on September 7, 2005, Amendment No. 6 to Schedule 13D filed with the Commission on September 29, 2005, Amendment No. 7 to Schedule 13D filed with the Commission on October 11, 2005, Amendment No. 8 to Schedule 13D filed with the Commission on October 14, 2005, Amendment No. 9 to Schedule 13D filed with the Commission on October 21, 2005, Amendment No. 10 to Schedule 13D filed with the Commission on October 27, 2005, Amendment No. 11 to Schedule 13D filed with the Commission on November 17, 2005, and Amendment No. 12 to Schedule 13D filed with the Commission on December 8, 2005 (as amended, the “Schedule 13D”). Capitalized terms used herein which are not defined herein have the meanings given to such terms in the Schedule 13D. Except as otherwise provided herein, all Items of the Schedule 13D remain unchanged.

Item 4. Purpose of the Transaction.

     Item 4 is hereby supplemented as follows:

     By letter dated January 27, 2006, Mr. James D. Dondero, a member of the Board of Directors (the “Board”) of Motient Corporation (the “Company”), whose principal business is serving as the President of the General Partner of Highland Capital Management, L.P., posed certain questions to the Board with respect to concerns Mr. Dondero has regarding recent SEC filings and the lack of information surrounding certain transactions. A copy of the letter from Mr. Dondero is attached hereto as Exhibit 99.8.

     In response to the foregoing actions, among others, the Reporting Persons are considering various plans or proposals which relate to or could result in the transactions or changes contemplated by Items 4(a) through 4(j) of Schedule 13D. Such plans or proposals could include acquisitions of additional shares in the open market or otherwise and potentially seeking possible changes in the present Board and management of the Company. In the interim and prior to formulating any definitive plan or proposal, the Reporting Persons may communicate with other stockholders regarding their concerns about the actions taken by the Company and its management.

Item 7. Material to be Filed as Exhibits.

     Item 7 is hereby amended and supplemented as follows:

Exhibit 99.8 Letter of James D. Dondero to the Board of Directors of Motient Corporation, dated January 27, 2006.

Page 14 of 16

SIGNATURE

     After reasonable inquiry and to the best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.

Date: January 27, 2006
	HIGHLAND CAPITAL MANAGEMENT, L.P.
	By:	Strand Advisors, Inc., its general partner
		By:	/s/ James Dondero
		Name:	James Dondero
		Title:	President
	STRAND ADVISORS, INC.
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
	/s/ James Dondero
	James Dondero
	PROSPECT STREET HIGH INCOME PORTFOLIO, INC.
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
	PROSPECT STREET INCOME SHARES INC.
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
	HIGHLAND LEGACY LIMITED
	By:	Highland Capital Management, L.P., its collateral manager
	By:	Strand Advisors, Inc., its general partner
		By:	/s/ James Dondero
		Name:	James Dondero
		Title:	President

Page 15 of 16

HIGHLAND CRUSADER OFFSHORE PARTNERS, L.P.
By:	Highland Crusader Fund GP, L.P., its general partner
By:	Highland Crusader GP, LLC, its general partner
By:	Highland Capital Management, L.P., its sole member
By:	Strand Advisors, Inc., its general partner
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
PAMCO CAYMAN, LIMITED
By:	Highland Capital Management, L.P., its collateral manager
By:	Strand Advisors, Inc., its general partner
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
HIGHLAND EQUITY FOCUS FUND, L.P.
By:	Highland Equity Focus Fund GP, L.P., its general partner
By:	Highland Equity Focus GP, LLC, its general partner
By:	Highland Capital Management, L.P., its sole member
By:	Strand Advisors, Inc., its general partner
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
HIGHLAND SELECT EQUITY FUND, L.P.
By:	Highland Select Equity Fund GP, L.P., its general partner
By:	Highland Select Equity GP, LLC, its general partner
By:	Highland Capital Management, L.P., its sole member
By:	Strand Advisors, Inc., its general partner
	By:	/s/ James Dondero
	Name:	James Dondero
	Title:	President
HIGHLAND CAPITAL MANAGEMENT SERVICES, INC.
By:	/s/ James Dondero
Name:	James Dondero
Title:	President

Page 16 of 16

APPENDIX I

     The name of each director and officer of HCM Services, Strand, Prospect Portfolio and Prospect Shares is set forth below. Unless otherwise indicated, the business address of each person listed below is Two Galleria Tower, 13455 Noel Road, Suite 800, Dallas, Texas 75240. Each person identified below is a citizen of the United States of America. The present principal occupation or employment of each of the listed persons is set forth below. During the past five years, none of the individuals listed below has been convicted in a criminal proceeding or been a party to a civil proceeding, in either case of the type specified in Items 2(d) or (e) of Schedule 13D.

	Present Principal Occupation or Employment
Name	and Business Address (if applicable)
Highland Capital Management Services, Inc.
James D. Dondero, Director	President
Mark K. Okada, Director	Executive Vice President
Patrick H. Daugherty	Secretary
Todd A. Travers	Assistant Secretary
J. Kevin Ciavarra	Assistant Secretary
David Lancelot	Treasurer
Chad Schramek	Treasurer
Strand Advisors, Inc.
James D. Dondero, Director	President
Mark K. Okada	Executive Vice President
R. Joseph Daugherty	Vice President
Todd A. Travers	Secretary
J. Kevin Ciavarra	Assistant Secretary
Chad Schramek	Treasurer
Prospect Street High Income Portfolio, Inc. and Prospect Street Income Shares Inc.
James D. Dondero, Director	President
Mark K. Okada	Executive Vice President
R. Joseph Daugherty, Director	Senior Vice President
M. Jason Blackburn	Secretary and Treasurer
Michael S. Minces	Chief Compliance Officer
Timothy K. Hui, Director	Associate Provost for Graduate Education of the Pennsylvania Biblical University, 48 Willow Green Drive, Churchville, Pennsylvania 18966
Scott F. Kavanaugh, Director	Private investments
James F. Leary, Director	Managing Director of Benefit Capital Southwest, Inc., 2006 Peakwood Drive, Garland, Texas 75044
Bryan A. Ward, Director	Senior Manager of Accenture, LLP, 3625 Rosedale, Dallas, Texas 75205

EX-99.8

EXHIBIT 99.8

January 27, 2006

Dear Board of Directors:

Today’s markets expect public companies to make complete and accurate public disclosure of all material developments. It is my understanding that our securities laws are designed to compel this disclosure to ensure that stockholders are kept well-informed of any such developments on a current basis. Despite my efforts, the Board of Directors of Motient Corporation (“Motient” or the “Company”) has persisted with an agenda that has not been disclosed to me and must leave its shareholders guessing as to the company’s intended direction.

As its volatile stock price suggests, we believe that Motient’s recent SEC filings have resulted in lots of head scratching among industry analysts, institutional investors and the broader markets. Indeed, it is unclear to us what direction, if any, the Company is now headed. The unusual chronology includes the following:

• September 22, 2005 — Motient files a Current Report on Form 8-K announcing that it had executed a non-binding letter of intent to engage in a transaction that would result in the consolidation of the ownership of Mobile Satellite Ventures LP (“MSV”) and TerreStar Networks Inc. (“TerreStar”) within Motient, whereby Motient would issue a large number of its shares to MSV and TerreStar shareholders (the “Proposed Transaction”). Motient also announces that the Proposed Transaction would likely lead to the spin-off of TerreStar to Motient stockholders.

• October 2005 — Motient makes numerous SEC filings defending its past actions in the face of Delaware and Texas litigation and pursuing an exchange offer with all holders of its Series A Preferred Stock.

• November 3, 2005 — Motient files a Form S-1 with the Securities and Exchange Commission acknowledging that the Proposed Transaction is still in the works, but offering no additional details as to the status of the Proposed Transaction.

• November 7, 2005 — Motient files a Current Report on Form 8-K announcing a stock buyback program, presumably in response to a precipitous decline in Motient’s stock price, which had hit a 52-week low on November 4 at $13.75/share.

• November 21, 2005 — Motient files another Current Report on Form 8-K refuting allegations as to mismanagement by the Board of Directors and stating that certain stockholders had offered support for the Board in its continued negotiation of the Proposed Transaction.

• Rajendra Singh and his family together acquired more than 13% of the outstanding shares of Motient in February 2005 in connection with their sale of a large stake in MSV to Motient. Singh, who agreed to serve as an advisor to Motient following his acquisition of Motient stock, is the developer and patent holder of significant wireless mobile communication technologies and is widely regarded as a leader in the field. From November 22 to December 9, 2005, Singh and his family begin a series of sales of Motient Common Stock through what Singh discloses to be part of a concerted 10b-5 trading program.

• December 12, 2005 — Motient announces the decision by the Federal Communications Commission (“FCC”) to grant 20 MHz of the 2 GHz (S Band) spectrum to TerreStar, a level at which Motient gleefully concludes “allows enough bandwidth to guarantee robust voice and data services for first responders, underserved areas and the mobile communications consumer.” Motient’s stock closes at a near-term high of $23.47/share.

• December 12, 2005 to January 12, 2006 — Raj Singh and his family continue their sales of shares of Motient stock.

• January 12, 2006 — Motient Director Gerald Kittner announces his contribution of shares of Motient stock to a charity.

• January 26, 2006 — After recovering to the mid-20’s, Motient’s stock price continues its recent downward drift to close at $20.65/share.

Although I continue to serve as a director, Motient’s Executive Committee has effectively managed the Company and its actions for the entire period outlined above. Like other stockholders, I am forced to speculate as to Motient’s business plans given the recent events. Is the Proposed Transaction still under consideration? If so, has the Company sought to renegotiate the exchange ratios announced in September? How has the FCC’s award of a full 20MHz of spectrum to TerreStar in December 2005 affected the Proposed Transaction? Additionally, in January 2006, MSV announced a $1 billion contract with Boeing to purchase satellites to build out its network. Does the Company support this? Where will MSV get the cash to pay for these satellites?

Also interesting is Raj Singh’s heavy selling in Motient shares since November 22, 2005. Over this period, Singh’s Form 4 filings reveal that he and his family have disposed of more than 4 million shares of Motient stock, albeit purportedly cloaked in a 10b-5 trading plan. Does Raj Singh know something about Motient’s plans that we do not know?

As a director, I have a right to know the answers to these questions, and as a stockholder, the management of Motient has an obligation to disclose fully and completely all material information in its possession. In addition, it is my understanding that the Company is obligated to update information previously disclosed to the market — such as statements made about the

Proposed Transaction — when that information is no longer accurate. Absent a return to normal corporate governance of the Company by its properly elected Board of Directors, in accordance with their fiduciary duties, I request that the Motient Board of Directors enlighten us as to the status of the Company, its plans and its future.

Sincerely,

/s/ James D. Dondero

James D. Dondero