Exhibit 10.20

Silicon Valley Bank

Amendment to Loan Documents

Borrower:    Sento Corporation
                      Sento Technical Services Corporation

Date:            May            , 2004

THIS AMENDMENT TO LOAN DOCUMENTSis entered into between Silicon Valley Bank ("Silicon") and the borrower named above ("Borrower").

The
Parties agree to amend the Loan and Security Agreement between them, dated April 15, 2003 (as otherwise amended, if at all, the "Loan Agreement"), as follows, effective as of
the date hereof. (Capitalized terms used but not defined in this Amendment shall have the meanings set forth in the Loan Agreement.)

1.Amended Schedule.The Schedule to the Loan Agreement is
hereby amended in its entirety to read as set forth in the Amended and Restated Schedule to Loan and Security Agreement of even date herewith.

2.Certain Provisions Only Applicable on Event of Default.The
provisions of Sections 4.3, 4.4 and 4.5 of the Loan Agreement shall only be applicable after the occurrence and during the continuance of an Event of Default.

3.Modification re Audits.The first sentence of
Section 5.4 of the Loan Agreement is hereby amended to read as follows:



4.Delete Termination Fee.The second and third sentences of
Section 6.2 of the Loan Agreement, which provide for a termination fee, are hereby deleted from the Loan Agreement.

5.Modified Provision re Interest Computation.The first
sentence of Section 9.1 of the Loan Agreement is hereby amended to read as follows:



6.Additional Definitions.The definitions on Exhibit A
hereto are hereby added to Section 8 of the Loan Agreement in alphabetical order.

7.Fee.In consideration for Silicon entering into this
Amendment, Borrower shall pay Silicon the fees set forth in the Amended and Restated Schedule to Loan and Security Agreement of even

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date
herewith. Such fees shall be non-refundable and in addition to all interest and other fees payable to Silicon under the Loan Documents. Silicon is authorized to charge said such fees
to Borrower's loan account.

8.Representations True.Borrower represents and warrants to
Silicon that all representations and warranties set forth in the Loan Agreement, as amended hereby, are true and correct.

9.General Provisions.This Amendment, the Loan Agreement, the
Schedule, any prior written amendments to the Loan Agreement or the Schedule signed by Silicon and Borrower, and the other written documents and agreements between Silicon and Borrower set forth in
full all of the representations and agreements of the parties with respect to the subject matter hereof and supersede all prior discussions, representations, agreements and understandings between the
parties with respect to the subject hereof. Except as herein expressly amended, all of the terms and provisions of the Loan Agreement, and all other documents and agreements between Silicon and
Borrower shall continue in full force and effect and the same are hereby ratified and confirmed.

|Borrower:                            |  | Silicon:                    
|------------------------------------ |  | ----------------------------
|SENTO CORPORATION                    |  | SILICON VALLEY BANK         
|By                                   |  | President or Vice President 
|By                                   |  | Secretary or Ass't Secretary
|Borrower:                            |  |                             
|SENTO TECHNICAL SERVICES CORPORATION | 
|By                                   |  | President or Vice President 
|By                                   |  | Secretary or Ass't Secretary

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Exhibit A  Additional Definitions

"Closing Date" is the date of this Amendment.

"Contingent Obligation" is, for any Person, any direct or indirect liability, contingent or not, of that Person for (i) any
indebtedness, lease, dividend, letter of credit or other obligation of another such as an obligation directly or indirectly guaranteed, endorsed, co-made, discounted or sold with recourse
by that Person, or for which that Person is directly or indirectly liable; (ii) any obligations for undrawn letters of credit for the account of that Person; and (iii) all obligations
from any interest rate, currency or commodity swap agreement, interest rate cap or collar agreement, or other agreement or arrangement designated to protect a Person against fluctuation in interest
rates, currency exchange rates or commodity prices; but "Contingent Obligation" does not include endorsements in the ordinary course of business. The amount of a Contingent Obligation is the stated or
determined amount of the primary obligation for which the Contingent Obligation is made or, if not determinable, the maximum reasonably anticipated liability for it determined by the Person in good
faith; but the amount may not exceed the maximum of the obligations under the guarantee or other support arrangement.

"Indebtedness" is (a) indebtedness for borrowed money or the deferred price of property or services, such as reimbursement and
other obligations for surety bonds and letters of credit, (b) obligations evidenced by notes, bonds, debentures or similar instruments, (c) capital lease obligations and
(d) Contingent Obligations.

"Investment" is any beneficial ownership of (including stock, partnership interest or other securities) any Person, or any loan, advance
or capital contribution to any Person.

"Loan Documents" means, collectively, the Loan Agreement, the Representations, and all other present and future documents, instruments and
agreements between Silicon and Borrower, including, but not limited to those relating to the Loan Agreement, and all amendments and modifications thereto and replacements therefor.

"Permitted Indebtedness" is: (a) Borrower's indebtedness to Silicon under this Agreement or any other Loan Document; (b)
Indebtedness existing on the Closing Date and shown on the Schedule; (c) Subordinated Debt; (d) Indebtedness to trade creditors incurred in the ordinary course of business; and (e)
Indebtedness secured by Permitted Liens.

"Permitted Investments" are: (a) Investments shown on the Schedule and existing on the Closing Date; and (b) (i) marketable
direct obligations issued or unconditionally guaranteed by the United States or its agency or any State maturing within 1 year from its acquisition, (ii) commercial paper maturing no
more than 1 year after its creation and having the highest rating from either Standard & Poor's Corporation or Moody's Investors Service, Inc., and (iii) Silicon's
certificates of deposit issued maturing no more than 1 year after issue.

"Representations" means the written Representations and Warranties provided by Borrower to Silicon referred to in the Schedule.

"Subsidiary" is for any Person, or any other business entity of which more than 50% of the voting stock or other equity interests is owned
or controlled, directly or indirectly, by the Person or one or more Affiliates of the Person.

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