Exhibit 10.17



|Debenture No.  |  |                       
|-------------- |  | ----------------------
|April 15, 2003 |  | $                  .00

Sento
Corporation, a Utah corporation (the "Company"), hereby promises to pay to the order
of                        
("Purchaser") or its registered assignee (Purchaser or such registered assignee being referred to herein as
"Holder") the principal amount of $                        .00 together with
interest thereon calculated from the date hereof in accordance with the provisions
of this debenture (this "Debenture").

This
Debenture is issued pursuant to the Subscription Agreement, dated as of April 15, 2003 (the "Subscription Agreement"), between
the Company and Purchaser. The Subscription Agreement contains
terms governing the rights of Holder, and all provisions of the Subscription Agreement relating to this Debenture are hereby incorporated herein in full by reference. This Debenture is issued as a
part of a series of 8% Convertible Subordinated Debentures pursuant to that certain Private Placement Memorandum of the Company, dated March 10, 2003, as amended (such debentures being
collectively, the "Debentures"). Certain defined terms used herein are defined in Section 8 below. Unless otherwise indicated herein, capitalized
terms used in this Debenture have the same meanings set forth in the Subscription Agreement.

1.Payment of Principal and Interest.



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2.Subordination. The indebtedness evidenced by this Debenture is an unsecured obligation of the Company and is hereby
expressly subordinated, to the extent and in the manner hereinafter set forth, in right of payment to the prior payment in full of all the Company's Senior Indebtedness, as hereinafter defined.



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3.Events of Default.



4.Conversion.



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5.Redemption.



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6.Prohibition on Dividends. Until the Expiration Date, the Company shall not declare nor pay any dividend with respect to
the Common Stock other than a stock dividend.

7.Amendment and Waiver. Except as otherwise expressly provided herein, the provisions of the Debenture may be amended and
the Company may take any action herein prohibited, or omit to perform any act herein required to be performed by it, only if the Company has obtained the written consent of Holder.

8.Definitions. For purposes of the Debenture, the following capitalized terms have the following meaning.

"Closing" means the closing of the offering of the Debentures.

"Closing Date" means the date of the Closing.

"Common Stock" means, collectively the Company's Common Stock, $0.25 par value, and any capital stock of any class of the Company
hereafter authorized which is not limited to a fixed sum or percentage of par or stated value in respect to the rights of the holders thereof to participate in dividends or in the distribution of
assets upon any liquidation, dissolution or winding up of the Company.

"Market Price" of any security means the average of the closing prices of such security's sales on all securities exchanges on which such
security may at the time be listed, or, if there has been no sales on any such exchange on any day, the average of the highest bid and lowest asked prices on all such exchanges at the end of such day,
or, if on any day such security is not so listed, the average of the representative bid and asked prices quoted in the NASDAQ System as of 4:00 P.M., New York time, or if on any day such
security is not quoted in the NASDAQ System, the average of the highest bid and lowest asked prices on such day in the domestic over-the-counter market as reported by the
National Quotation Bureau, Incorporated, or any similar successor organization, in each such case averaged over a period of 21 days consisting of the day as of which "Market Price" is being
determined and the 20

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consecutive
business days prior to such day. If at any time such security is not listed on any securities exchange or quoted in the NASDAQ System or the over-the-counter
market, the "Market Price" will be fair value thereof determined jointly by the Company and Holder. If such parties are unable to reach agreement within a reasonable period of time, such fair value
will be the fair value thereof as reasonably determined by the Company's Board of Directors.

"Person" means an individual, a partnership, a corporation, an association, a joint stock company, a trust, a joint venture, an
unincorporated organization and a governmental entity or any department, agency or political subdivision thereof.

"Subsidiary" means any corporation of which the shares of stock having a majority of the general voting power in electing the board of
directors are, at the time as of which any determination is being made, owned by the Company either directly or indirectly through Subsidiaries.

9.Transfer.



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10.Cancellation. After all principal and accrued interest at any time owned on the Debenture has been paid in full, the
Debenture will be surrendered to the Company for cancellation and will not be reissued.

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11.Place of Payment. Payments of principal and interest are to be delivered to the Purchaser as follows:



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

12.Governing Law. This Debenture shall be construed and interpreted according to the laws of the State of Utah without
giving effect to the principles of conflicts of law thereof.

IN
WITNESS WHEREOF, the Company has executed and delivered this Debenture on                        , 2003.

| |  | SENTO CORPORATION
| |  | -----------------
| |  | By:              
| |  |                  
| |  | Name:            
| |  |                  
| |  | Title:           
| |  |                  

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EXHIBIT ANOTICE OF CONVERSION

1.     The
undersigned holder of the attached debenture (the "Debenture") hereby elects to convert the outstanding principal of
the Debenture (together with accrued and unpaid interest thereon) into the number of shares of the Common Stock determined in accordance with the terms and conditions of the Debenture. Terms used but
not defined herein shall have the meaning set forth in the Debenture.

2.     Please
issue a certificate or certificates representing the Conversion Shares in the name of the undersigned.

(Date)

| | (SIGNATURE)         
| | --------------------
| | (PRINT OR TYPE NAME)

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EXHIBIT BASSIGNMENT FORM

Dated:

FOR
VALUE RECEIVED,                        ("Assignor") hereby sells, assigns, and
transfers unto                        (please type or print)
                        (address) the rights of Assignor under the debenture attached hereto (the "Debenture") to the extent of $            of the
outstanding principal amount of the Debenture and does hereby irrevocably constitute and appoint Sento Corporation (the "Company") and/or its transfer
agent as attorney to transfer the same on the books of the Company with full power of substitution in the premises.

| | (SIGNATURE)
| | -----------

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