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                                                                    Exhibit 10.8


                            REVOLVING PROMISSORY NOTE

September 7, 2001                                                       $45,899


                  Jack Pearlstein ("MAKER"), hereby promises to pay to the order
of DigitalNet Holdings, Inc. (the "COMPANY"), the aggregate unpaid principal
amount of this Note, together with interest thereon calculated from the date
hereof in accordance with the provisions of this Note.

                  This Note is the promissory note referred to in the Senior
Management Agreement, dated as of September 7, 2001, by and among the Company,
DigitalNet, Inc., a Delaware corporation, and Maker (the "MANAGEMENT
AGREEMENT"). Sections 1(a)(i), 1(b)(ii) and 2(b) of the Management Agreement
contain provisions for the issuance of this Note and increases and decreases of
the principal amount hereunder upon the terms and conditions specified therein.
Capitalized terms used herein and not otherwise defined shall have the meanings
given to them in the Management Agreement.

                  1. BORROWINGS UNDER NOTE. The date and amount of all loans
made by the Company to the Maker hereunder, the date and amount of each payment
of principal, and the date and amount of each payment of interest shall be noted
by the Company on SCHEDULE I annexed hereto and made a part hereof, or on a
continuation of such schedule attached hereto and made a part hereof; PROVIDED,
HOWEVER, that the failure of the Company to make, or any error in making, any
such notation shall not limit, expand or otherwise affect the obligations of the
Maker hereunder or under the Management Agreement.

                  2. PAYMENT OF INTEREST. Interest shall accrue on the
outstanding principal amount of this Note at a rate equal to the lesser of (i)
5% per annum and (ii) the highest rate permitted by applicable law, compounded
annually. Accrued interest shall be payable at such time as the principal of
this Note becomes due and payable. The Company may note such interest on
SCHEDULE I annexed hereto provided that any failure to note such amount shall
not change the obligation of the Maker to pay such amount.

                  3. PAYMENT OF PRINCIPAL ON NOTE.

                  (a) TERM. Subject to Section 3(b) below, the entire principal
amount of this Note and all accrued interest thereon shall be due and payable on
September ___, 2010.

                  (b) MANDATORY PREPAYMENTS. Upon the earlier of (i) a Liquidity
Event or (ii) a Public Offering, Maker shall pay the entire principal amount
then outstanding and any accrued interest to the Company. In addition, in the
event Maker receives any net cash proceeds in connection with his ownership of
the Reserved Stock, Maker shall prepay any amounts owed

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pursuant to this Note by applying all of such proceeds FIRST, to any accrued
interest and SECOND, to any principal then outstanding.

                  (c) OPTIONAL PREPAYMENTS. Maker may, at any time and from time
to time without premium or penalty, prepay all of the outstanding principal
amount of the Note; provided that any prepayment will be accompanied by a
payment of accrued interest on the portion being prepaid. A prepayment of less
than all of the outstanding principal amount of the Note shall not relieve Maker
of his obligation to make the payments on the Note pursuant to Sections 3(a) and
3(b) above.

                  (d) RIGHT OF OFFSET. The Maker shall be entitled to offset any
amounts owed to the Maker by the Company, now existing or hereinafter arising,
pursuant to and as set forth in Section 2 of the Management Agreement between
the Company and the Maker, against any amounts payable under this Note.
Following an Event of Default, the Company shall be entitled to offset any
amounts owed to the Company by the Maker, now existing or hereinafter arising,
pursuant to this Note against any amounts payable by the Company to the Maker
pursuant to and as set forth in the Management Agreement between the Company and
the Maker.

                  4. SECURITY.

                  (a) PLEDGE. The amounts due under this Note are secured by a
pledge of shares of the Company's Common Stock under the terms of the Executive
Stock Pledge Agreement of even date herewith between Maker and the Company, and
the payment of the principal amount and accrued interest under this Note is
subject to certain offset rights under the Management Agreement.

                  (b) RECOURSE. Notwithstanding anything herein or in any other
agreement, instrument or other document to the contrary, the Maker shall be
personally liable for the repayment of the indebtedness evidenced by this Note
or for any claim of any kind based thereon or relating thereto to the extent of
the first 50% of the amount of the Note. For the remaining 50% of the amount of
the Note, the Lender shall be entitled to and shall look solely to the Pledged
Shares (as defined in the Executive Stock Pledge Agreement of even date herewith
between Maker and the Company) as its sole and exclusive remedy, including,
without limitation, any cash or non-cash proceeds therefrom, for the repayment
of the indebtedness evidenced by this Note and any other claim of any kind
relating thereto or to the Executive Stock Pledge Agreement or arising hereunder
or thereunder. The payment of the principal amount and accrued interest under
this Note is subject to certain offset rights as set forth in Section 3(d)
above.

                  5. EVENTS OF DEFAULT.

                  (a) DEFINITION. For purposes of this Note, an Event of Default
         shall be deemed to have occurred if:

                           (i) Maker fails to pay when due, the full amount of
         any principal or interest payment, and such amount remains unpaid for 2
         business days following receipt of written notice from the Company; or

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                           (ii) Maker makes an assignment for the benefit of
         creditors or admits in writing his inability to pay his debts generally
         as they become due; or an order, judgment or decree is entered
         adjudicating Maker bankrupt or insolvent; or any order for relief with
         respect to Maker is entered under the Federal Bankruptcy Code; or Maker
         petitions or applies to any tribunal for the appointment of a
         custodian, trustee, receiver or liquidator of any substantial part of
         Maker's assets, or commences any proceeding relating to Maker under any
         bankruptcy, reorganization, arrangement, insolvency, readjustment of
         debt, dissolution or liquidation law of any jurisdiction; or any such
         petition or application is filed, or any such proceeding is commenced,
         against Maker and either (A) Maker by any act indicates its approval
         thereof, consent thereto or acquiescence therein or (B) such petition,
         application or proceeding is not dismissed within 60 days.

                  (b) CONSEQUENCES OF EVENTS OF DEFAULT. If an Event of Default
has occurred the aggregate principal amount of the Note (together with all
accrued interest thereon and all other amounts payable in connection therewith)
shall become immediately due and payable without any action on the part of the
Company, and Maker shall immediately pay to the Company all amounts due and
payable with respect to the Note.

                  Maker, or his successors and assigns, hereby waives diligence,
presentment, protest and demand and notice of protest and demand, dishonor and
nonpayment of this Note, and expressly agrees that this Note, or any payment
hereunder, may be extended from time to time and that the Company may accept
security for this Note or release security for this Note, all without in any way
affecting the liability of Maker hereunder.

                  In the event that Maker fails to pay any amounts due hereunder
when due, Maker shall pay to the Company, in addition to such amounts due, all
costs of collection, including, without limitation, reasonable attorneys fees.

                  6. AMENDMENT AND WAIVER. Except as otherwise expressly
provided herein, the provisions of the Note may be amended and Maker may take
any action herein prohibited, or omit to perform any act herein required to be
performed by it, only if Maker has obtained the written consent of the Company.

                  7. CANCELLATION. After all principal and accrued interest at
any time owed on this Note has been paid in full, this Note shall be surrendered
to Maker for cancellation and shall not be reissued.

                  8. PLACE OF PAYMENT. Payments of principal and interest are to
be delivered to the Company at the following address:

                           DigitalNet Holdings, Inc.
                           6700A Rockledge Drive, Suite 525
                           Bethesda, MD 20817
                           Attention:  President and Chief Executive Officer


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or to such other address or to the attention of such other person as specified
by prior written notice to Maker.

                  9. USURY LAWS. It is the intention of the Company and Maker to
conform strictly to all applicable usury laws now or hereafter in force, and any
interest payable under this Note shall be subject to reduction to the amount not
in excess of the maximum legal amount allowed under the applicable usury laws as
now or hereafter construed by the courts having jurisdiction over such matters.
If the maturity of this Note is accelerated by reason of an election by the
Company resulting from an Event of Default, voluntary prepayment by Maker or
otherwise, then earned interest may never include more than the maximum amount
permitted by law, computed from the date hereof until payment, and any interest
in excess of the maximum amount permitted by law shall be canceled automatically
and, if theretofore paid, shall at the option of the Company either be rebated
to Maker or credited on the principal amount of this Note, or if this Note has
been paid, then the excess shall be rebated to Maker. The aggregate of all
interest (whether designated as interest, service charges, points or otherwise)
contracted for, chargeable, or receivable under this Note shall under no
circumstances exceed the maximum legal rate upon the unpaid principal balance of
this Note remaining unpaid from time to time. If such interest does exceed the
maximum legal rate, it shall be deemed a mistake and such excess shall be
canceled automatically and, if theretofore paid, rebated to Maker or credited on
the principal amount of this Note, or if this Note has been repaid, then such
excess shall be rebated to Maker.

                  10. GOVERNING LAW. This Note is made under and governed by the
internal law, not the laws of conflicts, of the State of Delaware.


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                  IN WITNESS WHEREOF, Maker has executed and delivered this Note
as of the date above.


                                                     /s/ JACK PEARLSTEIN
                                                     ---------------------------
                                                     JACK PEARLSTEIN


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