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Exhibit 10.20

SECOND LOAN MODIFICATION AGREEMENT

        This Loan Modification Agreement is entered into as of May 14, 2003 by
and between WITNESS SYSTEMS, INC., a Delaware corporation ("Borrower"), whose
address is 300 Colonial Center Parkway, Roswell, Georgia 30076, and SILICON
VALLEY BANK ("Lender"), a California-chartered bank with a principal place of
business at 3003 Tasman Drive, Santa Clara, CA 95054 and with a loan production
office located at 3343 Peachtree Road, Suite 312, Atlanta, GA 30326.

        WHEREAS, among other indebtedness which may be owing by Borrower to
Lender, Borrower is indebted to Lender pursuant to, among other documents, a
Loan and Security Agreement, dated April 3, 2002, as may be amended from time to
time, in the original principal amount of Fifteen Million Dollars ($15,000,000)
(the "Loan Agreement"; the Loan Agreement together with all other documents
evidencing or securing the indebtedness shall be referred to as the "Existing
Loan Documents");

        WHEREAS, the Loan Agreement provides for, among other things, a
Committed Line in the original principal amount of Fifteen Million Dollars
($15,000,000) (hereinafter, all indebtedness owing by Borrower to Lender shall
be referred to as the "Indebtedness");

        WHEREAS, pursuant to the Loan Agreement, Borrower agreed, among other
things, to comply with certain covenants set forth therein, including certain
financial covenants; and

        WHEREAS, Borrower has requested that Lender waive certain financial
covenants, and Lender is willing to do so, subject to the terms and conditions
set forth herein, including the amendment to the Loan Agreement set forth
herein.

        NOW, THEREFORE, in consideration of the foregoing premises, and other
good and valuable consideration, the receipt and legal sufficiency of which is
hereby acknowledged, the parties hereto hereby agree as follows:

        1.    DEFINITIONS.    All capitalized terms used herein and not
otherwise defined shall have the meanings given to such terms in the Loan
Agreement.

        2.    WAIVER OF COVENANT VIOLATION.    In reliance upon the
representations, warranties, agreements and covenants of Borrower set forth
herein and in the Loan Agreement, as amended hereby, Lender herby waives any
Event of Default arising solely out of Borrower's failure to have as of
March 31, 2003 the Consolidated Tangible Net Worth required by
Section 6.7(ii) of the Loan Agreement.

        3.    MODIFICATIONS TO LOAN AGREEMENT.    

        3.1   The Loan Agreement is amended by deleting Section 2.2 in its
entirety and by substituting therefor a new Section 2.2 to read as follows:

        If Borrower's Obligations under Section 2.1.1, 2.1.2 and 2.1.3 exceed
the lesser of either (i) the Committed Revolving Line or (ii) the Borrowing
Base, Borrower shall upon notice from Bank, immediately pay such excess or
secure such excess with a pledge of cash maintained at Bank.

        3.2   The Loan Agreement is amended by deleting paragraph (ii) of
Section 6.7 in its entirety and by substituting therefor a new paragraph (ii) to
read as follows:

        (ii)   Consolidated Tangible Net Worth. A Consolidated Tangible Net
Worth of at least the sum of (a) $20,000,000, plus (b) seventy-five percent of
net income (without subtracting any losses) earned in each fiscal quarter from
and after March 31, 2003, plus (c) fifty percent

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(50%) of the net cash proceeds from any equity issued from and after May 14,
2003 by Borrower, calculated after subtracting any cash consideration received
from such issuance which is used to finance an acquisition; provided, however,
at any time that the Quick Ratio is less than 2.0 to 1.0, this covenant will be
tested on a monthly basis.

        3.3   The Loan Agreement is hereby amended by deleting Exhibit D thereof
in its entirety and substituting therefor a new Exhibit D in the form attached
hereto.

        4.    CONSISTENT CHANGES.    The Existing Loan Documents are hereby
amended wherever necessary to reflect the changes described above.

        5.    NO DEFENSES OF BORROWER.    Borrower agrees that it has no
defenses against the obligations to pay any amounts under the Indebtedness.

        6.    CONTINUING VALIDITY.    Borrower understands and agrees that in
modifying the existing Indebtedness, Lender is relying upon Borrower's
representations, warranties, and agreements, as set forth in the Existing Loan
Documents. Except as expressly modified pursuant to this Loan Modification
Agreement, the terms of the Existing Loan Documents remain unchanged and in full
force and effect. Lender's agreement to modifications to the existing
Indebtedness pursuant to this Loan Modification Agreement in no way shall
obligate Lender to make any future modifications to the Indebtedness. Nothing in
this Loan Modification Agreement shall constitute a satisfaction of the
Indebtedness. It is the intention of Lender and Borrower to retain as liable
parties all makers and endorsers of Existing Loan Documents, unless the party is
expressly released by Lender in writing. No maker, endorser, or guarantor will
be released by virtue of this Loan Modification Agreement. The terms of this
paragraph apply not only to this Loan Modification Agreement, but also to all
subsequent loan modification agreements.

        7.    LIMITATION.    This Loan Modification Agreement is limited to the
matters expressly set forth above and shall not be deemed to waive or modify any
other term of the Loan Agreement or Loan Documents, each of which is hereby
ratified and reaffirmed, or to consent to any subsequent failure of Borrower to
comply with any term or provision of the Loan Agreement or the Loan Documents,
each of which shall remain in full force and effect.

        8.    CONDITIONS.    The effectiveness of this Loan Modification
Agreement is conditioned upon Borrower's execution and delivery of this Loan
Modification Agreement and such other instruments, documents and agreements as
Lender or its counsel shall request.

[signatures appear on following page]

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        This Loan Modification Agreement is executed as of the date first
written above.

    LENDER:
 
 
SILICON VALLEY BANK:
 
 
By:
       

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    Name:        

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    Title:        

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    BORROWER:
 
 
WITNESS SYSTEMS, INC.
 
 
By:
       

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    Name:        

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    Title:        

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EXHIBIT D
COMPLIANCE CERTIFICATE

TO:   SILICON VALLEY BANK
3003 Tasman Drive
Santa Clara, CA 95054
FROM:
 
Witness Systems, Inc.

        The undersigned authorized officer of Witness Systems, Inc. ("Borrower")
certifies that under the terms and conditions of the Loan and Security Agreement
between Borrower and Bank (the "Agreement"), (i) Borrower is in complete
compliance for the period ending                        with all required
covenants except as noted below and (ii) all representations and warranties in
the Agreement are true and correct in all material respects on this date.
Attached are the required documents supporting the certification. The Officer
certifies that these are prepared in accordance with Generally Accepted
Accounting Principles (GAAP) consistently applied from one period to the next
except as explained in an accompanying letter or footnotes. The Officer
acknowledges that no borrowings may be requested at any time or date of
determination that Borrower is not in compliance with any of the terms of the
Agreement, and that compliance is determined not just at the date this
certificate is delivered.

Please indicate compliance status by circling Yes/No under "Complies" column.

Reporting Covenant

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  Required

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  Complies

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Quarterly financial statements + CC   Quarterly within 45 days
(Monthly if QR below 2.0:1.0)         
Yes No Annual (Audited)   FYE within 90 days       Yes No 10-K & 10Q   Within 5
days of filing       Yes No A/R Agings   Monthly within 30 days
(if Advances outstanding)        
Yes No A/R Audit   Annual       Yes No Borrowing Base Certificate   Monthly
within 30 days
(if Advances outstanding)       Yes No Financial Covenant

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  Required

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  Actual

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  Complies

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Maintain on a quarterly Basis or monthly if QR below 2.0:1.0:              
Minimum Quick Ratio   1.50:1.00           :1.00   Yes No   Minimum Tangible Net
Worth   $20,000,000,
Plus 75% of Net Income,
Plus 50% of Net Cash Equity   $   Yes No

        Have there been updates to Borrower's intellectual property, if
appropriate?            Yes / No

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Comments Regarding Exceptions: See Attached.

    BANK USE ONLY Sincerely,   Received by:            

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AUTHORIZED SIGNER

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SIGNATURE   Date:            

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        Verified:        

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AUTHORIZED SIGNER

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TITLE   Date:            

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DATE:   Compliance Status:                        Yes No

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Exhibit 10.20

SECOND LOAN MODIFICATION AGREEMENT