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                                                                   EXHIBIT 10.20

                                   May 6, 2004

David McTarnaghan
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            RE:   RETENTION BONUS AGREEMENT

Dear Mr. McTarnaghan:

            I am pleased to inform you that you have been selected to be
eligible to receive a retention bonus if you continue to be employed by Daleen
Technologies, Inc. (the "Company") through May 6, 2005 or, if earlier, the date
of the completion of a merger between the Company and Daleen Holdings, Inc. This
letter sets out the terms and conditions of the retention bonus arrangement (the
"Agreement") between you and the Company.

            For purposes of this Agreement, "Merger Transaction" means the
completion of the merger of the Company with and into a subsidiary of Daleen
Holdings, Inc., in accordance with the terms of a merger agreement among the
Company, Daleen Holdings, Inc. and certain other parties. For purposes of this
Agreement, the terms "Cause" and "Good Reason" are defined in your employment
agreement with the Company, dated July 22, 1998, as amended, and as it may be
further amended.

      1.    RIGHT TO PAYMENT.

            (a)   Subject to the terms and conditions of this Agreement, you
will be entitled to receive an amount equal to $25,000 if you continue to be
employed by the Company through May 6, 2005, or, if earlier, the date that the
Merger Transaction closes. If a payment becomes due under this paragraph 1(a),
the payment will be made in a single lump sum payment, net of all Federal,
state, local, or other taxes as are required to be withheld, within thirty (30)
days after the payment becomes due.

            (b)   The Board of Directors of the Company (the "Board") will have
the sole and absolute authority and discretion to determine whether and when the
Merger Transaction has closed. The Board's decision will be binding on all
parties.

      2.    EFFECT OF TERMINATION.

            (a)   If, prior to the date that you become entitled to a payment
under Paragraph 1 of this Agreement, your employment with the Company is
terminated by the Company without "Cause" or you resign with "Good Reason," you
will be entitled to receive the retention bonus set forth in Paragraph 1 of this
Agreement, payable in a single lump sum

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payment, net of all Federal, state, local, or other taxes as are required to be
withheld, within thirty (30) days after the effective date of your termination
or resignation.

            (b)   If, prior to the date that you become entitled to a payment
under Paragraph 1 of this Agreement, your employment with the Company is
terminated for any reason other than as described in Paragraph 2(a) of this
Agreement, you will have no right to receive a payment under this Agreement.

      3.    BINDING EFFECT. This Agreement is personal to you and without the
prior written consent of the Company will not be assignable by you otherwise
than by will or the laws of descent and distribution. This Agreement will inure
to the benefit of and be enforceable by your legal representatives. This
Agreement will inure to the benefit of and be binding upon the Company and its
successors and assigns.

      4.    EMPLOYMENT STATUS. This Agreement will not be deemed to create in or
confer upon you any right to be retained in the employ of the Company or any
subsidiary or other affiliate thereof.

      5.    ENTIRE AGREEMENT. This Agreement contains the entire understanding
of the Company and you with respect to the subject matter hereof.

      6.    SEVERABILITY. In the event any provision of this Agreement will be
held illegal or invalid for any reason, the illegality or invalidity will not
affect the remaining parts of the Agreement, and the Agreement will be construed
and enforced as if the illegal or invalid provision had not been included.
Further, the captions of this Agreement are not part of its provisions and will
have no force and effect.

      7.    AMENDMENT AND TERMINATION. This Agreement may be amended or
terminated at any time by written agreement of the parties hereto.

      8.    APPLICABLE LAW. To the extent not preempted by the laws of the
United States, the laws of the State of Florida, other than the conflict of law
provisions thereof, will be the controlling law in all matters relating to this
Agreement.

                                            Yours truly,

                                            DALEEN TECHNOLOGIES, INC.

                                            By: /s/ Gordon Quick
                                                -----------------------
                                            Title: President & CEO

ACCEPTED AND ACKNOWLEDGED:

/s/ David McTarnaghan
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Name:  David McTarnaghan

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