Exhibit 10.17a

CONFIRMATION OF GUARANTY  BY  PRIMAL SOLUTIONS, INC.

THIS CONFIRMATION OF GUARANTY (this "Agreement") is given on this 27th day of March 2004 by
PRIMAL SOLUTIONS, INC. ("Guarantor"), to Lightbridge, Inc. ("Beneficiary").

RECITALS:

A.    Wireless
Billing Systems, a California corporation ("Wireless"), 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");

B.    Wireless
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");

C.    Wireless
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;

D.    Beneficiary
succeeded to the assets and liabilities of Corsair by way of merger;

E.    Wireless
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 Beneficiary (the "2002 Amended Note"), which amended and
restated the December 2001 Amended Note;

F.     Guarantor
executed that certain Guaranty dated as of December 27, 2002 in favor of Beneficiary in order to induce Beneficiary to agree to the revised payment terms
reflected in the 2002 Amended Note;

G.    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;

H.    Wireless
has requested that the terms reflected in the 2002 Amended Note be revised in order to reflect a different repayment schedule for the outstanding debt evidenced
thereby, all as set forth more fully in the 2004 Amended and Restated Secured Promissory Note (the "2004 Amended Note"); and

I.     Beneficiary
desires to obtain the acknowledgment and consent of Guarantor to the 2004 Amended Note and the confirmation by Guarantor of its obligations under the Guaranty
as a condition to accepting the 2004 Amended Note.

NOW,
THEREFORE, Guarantor hereby represents, warrants, certifies and agrees in favor of Beneficiary as follows:



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IN
WITNESS WHEREOF, Guarantor has caused this Agreement to be duly executed as of the day and year first above written.

| |  | PRIMAL SOLUTIONS, INC.
| |  | ----------------------
| |  | By:                   

Accepted
as of the
date below written:

|       | LIGHTBRIDGE, INC..     
|------ | -----------------------
|By:    | /s/ HARLAN PLUMLEY     
|Name:  | Harlan Plumley         
|Title: | Chief Financial Officer
|Date:  | March 26, 2004         

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