Exhibit 10.17

2004 AMENDED AND RESTATED SECURED PROMISSORY NOTE

|              |  |                          
|------------- |  | -------------------------
|$1,509,919.00 |  | Irvine, CA
March 27, 2004

WHEREAS,
Wireless Billing Systems, a California corporation ("Wireless Billing;" "Maker"), executed that certain Secured Promissory Note dated May 26, 1999, in the principal
amount of Two Million Two Hundred Thirty-Eight Thousand Two Hundred Forty-Two Dollars ($2,238,242.00) in favor of Corsair Communications, Inc. ("Corsair") (the "Original Note");

WHEREAS,
Wireless Billing executed that certain Note Agreement dated as of January 1, 2001 (the "Note Agreement"), and that certain Amended and Restated Secured Promissory Note on
January 1, 2001, in the principal amount of One Million Six Hundred Ninety-Six Thousand Three Hundred Ninety-Four Dollars and Eighteen Cents ($1,696,394.18) in favor of
Corsair (together, the "January 2001 Amended Note");

WHEREAS,
Wireless Billing and Corsair executed a letter agreement dated December 20, 2001, revising the terms of the January 2001 Amended Note. The January 2001
Amended Note, as amended
by said letter agreement (the "December 2001 Amended Note"), amended and restated the Original Note;

WHEREAS,
Lightbridge, Inc. ("Holder") succeeded to the assets and liabilities of Corsair by way of merger;

WHEREAS,
Maker executed that certain 2002 Amended and Restated Secured Promissory Note dated December 27, 2002, in the principal amount of One Million Seven Hundred
Twenty-Two Thousand Four Hundred Seventeen Dollars ($1,722,417.00) in favor of Holder (the "2002 Amended Note"), which amended and restated the December 2001 Amended Note;

WHEREAS,
the balance of all outstanding principal and accrued but unpaid interest under the 2002 Amended Note on the date hereof is One Million Five Hundred Nine Thousand Nine Hundred
Nineteen Dollars ($1,509,919.00) and the 2002 Amended Note matures on December 26, 2004; and

WHEREAS,
Maker and Holder desire to amend and restate the 2002 Amended Note as provided herein.

NOW
THEREFORE:

FOR
VALUE RECEIVED, Maker hereby promises to pay to the order of Holder, at 67 South Bedford Street, Burlington, Massachusetts 01803, or at such other place as Holder may designate from
time to time in writing, in lawful money of the United States of America and in immediately available funds, the principal amount of One Million Five Hundred Nine Thousand Nine Hundred Nineteen
Dollars ($1,509,919.00), together with interest accrued on the unpaid principal amount hereof from the date hereof at the rate of eight percent (8%) per annum, compounded annually, payable as follows:



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"Financing"
shall mean the closing of the next investment financing transaction by Maker of the sale and primary issuance of its securities to one or more unaffiliated third party(ies)
in a transaction or series of related transactions in consideration of gross cash proceeds received by Maker in an aggregate amount of not less than Three Million Dollars ($3,000,000) as payment by
investors of the purchase price for the securities issued by Maker as part of the financing transaction where such investors hold the same rights, preferences, terms and conditions as the other with
respect to said securities. Notwithstanding subparagraph (ii) above, Maker shall have no obligation to pursue or close any such Financing, nor shall it have any obligation to consult with
Holder regarding the terms of any possible Financing, nor shall Holder have any right to require any term or condition be included in any such Financing;provided,
however, that nothing in this paragraph or in clause (ii) above shall be deemed to limit, restrict, or otherwise modify any rights and remedies that Holder may otherwise
have under the terms of this 2004 Amended and Restated Secured Promissory Note ("2004 Amended Note") or under applicable laws upon the occurrence of an Event of Default hereunder, including, without
limitation, in the event that the Financing results in a situation described in paragraph (c) or paragraph (d) of the definition of "Event of Default" hereunder.

Upon
payment in full of the outstanding principal and all accrued but unpaid interest thereon, this 2004 Amended Note shall be surrendered to Maker for cancellation.

Except
as otherwise set forth herein, all payments on this 2004 Amended Note shall be applied first against accrued and unpaid interest and then against the outstanding principal. Maker
shall have the right to prepay all or any portion of the principal obligation hereunder without penalty at any time or from time to time.

Maker
hereby waives presentment, demand for payment, notice, protest and all other demands and notices in connection with the delivery, acceptance, performance, default or enforcement of
this 2004
Amended Note. Maker hereby promises to pay on demand all reasonable legal fees and other costs and expenses paid or incurred by Holder in enforcing or collecting this 2004 Amended Note.

The
occurrence of any of the following events is an "Event of Default" hereunder:



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Upon
the occurrence of any Event of Default, all obligations hereunder shall become immediately due and payable.

In
case any Event of Default shall have occurred, Holder may proceed to protect and enforce its rights hereunder by suit in equity, action at law or any other appropriate proceeding.

Neither
any course of dealing by Holder nor any failure or delay by Holder to exercise any right, power or privilege hereunder shall operate as a waiver hereunder, and any single or
partial exercise of any such right, power or privilege shall not preclude any later exercise thereof or any exercise of any other right, power or privilege hereunder. No covenant, obligation or other
provision hereof may be waived by Holder and no consent contemplated hereby may be given by Holder other than in a writing signed by Holder explicitly waiving such covenant, obligation or provision or
giving such consent. If at any time any applicable usury law would ever render usurious any amounts called for hereunder, then it is Holder's and Maker's express intention that Maker shall not be
required to pay interest on this 2004 Amended Note at a rate in excess of the maximum lawful rate, that the provisions of this paragraph shall control over all other provisions of this 2004 Amended
Note which may be in apparent conflict hereunder, that such excess amount shall be immediately credited on the principal balance of this 2004 Amended Note (or, if this 2004 Amended Note has been fully
paid, refunded by Holder to Maker), and the provisions hereof shall be immediately reformed and the amounts thereafter collectible under this 2004 Amended Note reduced, without the necessity of the
execution of any further documents, so as to comply with the then-applicable law, but so as to permit the recovery of the fullest amount otherwise called for hereunder. Any such crediting
or refund shall not cure or waive any default by Maker under this 2004 Amended Note. If at any time following any reduction in the interest rate payable by Maker there remains unpaid any principal
amount under this 2004 Amended Note and the maximum interest rate allowed by applicable law is increased or eliminated, then the interest rate payable under this 2004 Amended Note shall be readjusted,
to the extent not prohibited by applicable law, so that the total dollar amount of interest payable hereunder shall be equal to the dollar amount of interest which would have been paid by Maker
without giving effect to the reduction in interest resulting from compliance with applicable usury laws.

This
2004 Amended Note amends and restates (and does not constitute an extinguishment or novation of) the Original Note, the December 2001 Amended Note and the 2002 Amended Note,
copies of which are attached hereto as Exhibits A, B and C, respectively, and each of which is hereby acknowledged by Maker as a true, correct, and complete copy of the original. This 2004 Amended
Note amends and restates the Original Note, the December 2001 Amended Note and the 2002 Amended Note, and does not evidence or effect a refinancing of all or any portion of the indebtedness
evidenced thereby, a release or relinquishment of the priority of the security interest of Holder in any assets (real and personal) of Maker, including without limitation pursuant to the Security
Agreement (as hereinafter defined).

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This
2004 Amended Note may not be changed, modified, amended or terminated except in a writing signed by Maker and Holder. The covenants and agreements contained in this 2004 Amended
Note shall bind Maker, and the rights hereunder shall inure to the benefit of the respective successors and assigns of Holder. This 2004 Amended Note shall not be transferred or assigned to any third
party, except:



Provided, however, in no event shall Holder transfer or assign this 2004 Amended Note to any person or entity engaging in any business which is or may
be competitive with the business of Maker or any of its affiliates. For the purposes hereof, the "business of Maker or any its affiliates" shall mean (i) the development, licensing, rental,
marketing or selling of software that performs mediation, rating or billing functions for communication service providers, and (ii) upon Maker's written notice to Holder, such other
business(es) as Maker or any of its affiliates may engage in from time to time. In the event that Holder transfers or assigns this 2004 Amended Note pursuant to paragraphs (2) or
(3) above, Holder shall provide Maker with prompt written notice of such transfer or assignment.

This
2004 Amended Note shall be governed by, interpreted under, and construed and enforced in accordance with, the laws of the State of California.

The
indebtedness evidenced by this 2004 Amended Note is secured by and pursuant to that certain Security Agreement, dated as of May 26, 1999, between Wireless Billing and Corsair
(the "Security Agreement").

[THE
REMAINDER OF THIS PAGE LEFT BLANK INTENTIONALLY]

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IN
WITNESS WHEREOF, the undersigned have executed this 2004 Amended Note as an instrument under seal as of the date first set forth above.

| |  | "MAKER:"                
| |  | ------------------------
| |  |                         
| |  | WIRELESS BILLING SYSTEMS
| |  | By:                     
| |  |                         
| |  | "HOLDER:"               
| |  |                         
| |  | LIGHTBRIDGE, INC.       
| |  | By:                     

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EXHIBIT A TO 2004 AMENDED NOTE

"ORIGINAL
NOTE"

[ATTACH
COPY OF MAY 26, 1999 NOTE]

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EXHIBIT B TO 2004 AMENDED NOTE

"DECEMBER
2001 AMENDED NOTE"

[ATTACH
COPY OF JANUARY 1, 2001 AMENDED NOTE
AND DECEMBER 20, 2001 LETTER AGREEMENT]

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EXHIBIT C TO 2004 AMENDED NOTE

"2002
AMENDED NOTE"

[ATTACHED
COPY OF DECEMBER 27, 2002 AMENDED NOTE]

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