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                                                                   EXHIBIT 10.12

                          TRANSACTION SUPPORT AGREEMENT

      This Transaction Support Agreement (this "Agreement"), dated as of May 7,
2004, is by and among Quadrangle Capital Partners LP, a Delaware limited
partnership ("QCP"), Quadrangle Select Partners LP, a Delaware limited
partnership ("QSP"), Quadrangle Capital Partners-A LP, a Delaware limited
partnership ("QCP-A" and together with QCP and QSP, the "Quadrangle Entities"),
Daleen Technologies, Inc., a Delaware corporation ("Daleen"), Daleen Holdings,
Inc., a newly formed Delaware corporation that is a wholly owned subsidiary of
Daleen ("Newco"), Behrman Capital II, L.P., a Delaware limited partnership
("Behrman"), Strategic Entrepreneur Fund II, L.P., a Delaware limited
partnership ("SEF"), Protek Telecommunications Solutions Ltd., a corporation
organized under the laws of England and Wales, whose principal place of business
is located at 1 York Road, Maidenhead, Berkshire, United Kingdom ("Protek"),
Paul A. Beaumont ("Beaumont"), Geoff Butcher ("Butcher"), and Ian Watterson
("Watterson"). The Quadrangle Entities, Daleen, Newco and Protek are referred to
in this Agreement as the "Specified Parties" and, together with the other
parties to this agreement, the "Parties".

      Concurrent with the execution and delivery of this Agreement, the Parties
are entering into and delivering (a) a Stock Purchase Agreement by and among
Newco, Protek, Beaumont, Butcher, Watterson and the other shareholders of Protek
(the "Protek Agreement"), (b) an Agreement and Plan of Merger by and among
Daleen, Newco and Parallel Acquisition, Inc., a wholly owned subsidiary of Newco
("Acquisition Sub") (the "Daleen Agreement"), and (c) an Investment Agreement by
and among Newco, the Quadrangle Entities, Behrman and SEF (the "Investment
Agreement" and, together with the Protek Agreement and the Daleen Agreement, the
"Transaction Agreements"). The Parties are entering into this Agreement for the
purpose of coordinating the performance and consummation of the transactions
contemplated by Transaction Agreements and to impose certain restrictions on the
exercise of termination rights and waiver of conditions under the Transaction
Agreements.

      The Parties therefore, in consideration of the mutual covenants set forth
herein and in the Transaction Agreements, hereby agree as follows:

      1.    Concurrent Closings. The consummation of the transactions
contemplated by the Transaction Agreements shall occur on the second business
day after the satisfaction and waiver (as provided herein and therein) of each
of the conditions set forth in Article VII of the Daleen Agreement, Sections 8
and 9 of the Protek Agreement and Section 6 of the Investment Agreement (other
than conditions that may only be satisfied by deliveries to be made at the
respective closings) at the offices of Kirkpatrick & Lockhart LLP located at 599
Lexington Avenue, New York, New York at 11 a.m., local time, or such other time
and place as the Specified Parties may agree. None of the transactions
contemplated by any Transaction Agreement shall be, nor be deemed to have been,
consummated unless the transactions contemplated by each other Transaction
Agreement shall have been or are simultaneously being consummated.

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      2.    No Exercise of Certain Termination Rights. No Specified Party shall
exercise the rights of termination provided under (a) Section 12.1(i) of the
Protek Agreement, (b) Section 8.01(a) of the Daleen Agreement, or (c) Section
9.3(a) of the Investment Agreement without the prior written consent of each
other Specified Party. Newco shall not exercise the termination rights provided
under Sections 8.01(e) or (f) of the Daleen Agreement without the prior written
consent of each other Specified Party other than Daleen.

      3.    Cross-Termination. Upon termination of any Transaction Agreement in
accordance with both the terms of such Transaction Agreement and this Agreement,
the Parties effecting such termination shall provide prompt written notice to
the other Parties to the address set forth on the signature pages hereto and the
Parties shall cause each other Transaction Agreement to terminate. Upon such a
termination of all Transaction Agreements, this Agreement shall terminate and be
of no further force and effect.

      4.    No Amendments. No material representation, warranty, condition,
covenant or agreement set forth in any Transaction Agreement shall be amended,
waived or modified without the prior written consent of each Specified Party (it
being understood that the updating of schedules provided for under any
Transaction Agreement shall not of itself constitute such an amendment, waiver
or modification). The foregoing shall not be deemed to limit or modify the
rights of any Party to withhold consent to the amendment of any Transaction
Agreement in accordance with its terms.

      5.    No Waivers. No material condition of any Specified Party to the
performance of that party's obligations under a Transaction Agreement shall be
waived by that Specified Party without the prior written consent of the other
Specified Parties.

      6.    Further Assurances. Each Party shall use all reasonable efforts to
take or cause to be taken all actions, and to do or cause to be done all other
things, necessary, proper or advisable in order for such Party to fulfill and
perform its obligations in respect of this Agreement and each of the Transaction
Agreements to which it is a party, or otherwise to consummate and make effective
the transactions contemplated by the Transaction Agreements.

      7.    SEC Transaction Filings. Each Party shall cooperate with Daleen as
may be reasonably requested by it in connection with the preparation, filing and
mailing of the SEC Transaction Filings (as such term is defined in the Daleen
Agreement), including provision of such information as may be necessary or
reasonably requested for inclusion therein. The information to be provided by
each other Party to Daleen for inclusion in any SEC Transaction Filing will be
true and correct and will not, neither at the time such information is provided
to Daleen nor when the definitive SEC Transaction Filings are filed with the SEC
and mailed to Daleen stockholders, contain any untrue statement of a material
fact or omit to state any material fact required to be stated therein or
necessary in order to make the statements therein, in light of the circumstances
under which they were made, not misleading. Each Party shall provide prompt
notice to Daleen of any change that makes or is reasonably likely to make such
information untrue or misleading, and shall cooperate with Daleen in the
preparation, filing and mailing of any amendments to an SEC Transaction Filing
made necessary or desirable by such developments.

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      8.    Representations of Each Party. Each Party hereby represents and
warrants to each other Party as follows:

            (a)   Such Party has full power and authority to enter into this
Agreement and the other Transaction Agreements and to perform fully its
obligations hereunder and thereunder and to consummate the transactions
contemplated hereby and thereby. If an entity, such entity has been duly
organized under the applicable laws of its jurisdiction of organization. The
execution and delivery of this Agreement and the other Transaction Agreements
and the performance by such Party of its obligations hereunder and thereunder
and the consummation of the transactions contemplated hereby and thereby have
been duly and validly authorized by all necessary action on the part of such
Party, including, if an entity, all necessary action of its equityholders and
its directors or comparable governing body. Each of this Agreement and the other
Transaction Agreements is a valid and binding obligation of such Party,
enforceable against it in accordance with its terms, subject to bankruptcy,
insolvency, fraudulent conveyance and transfer, reorganization, receivership,
moratorium, and other similar laws affecting the rights and remedies of
creditors generally and to the general principles of equity.

      (b)   Except as disclosed in any Transaction Agreement or the applicable
schedule thereto, neither the execution, delivery or performance of this
Agreement and the other Transaction Agreements nor the consummation of the
transactions contemplated hereby and thereby, with or without the giving of
notice or passage of time, or both, will violate, or result in any breach of, or
constitute a default under, or result in the imposition of any encumbrance upon
any asset of such Party pursuant to any provision of its charter, bylaws or
other charter or governing instrument or agreement, or any statute, rule or
regulation, or other agreement, document or instrument by which the Company is
bound or to which it or any of its properties are subject.

      (c)   Except as disclosed in any Transaction Agreement or the applicable
schedule thereto, there is no litigation or governmental proceeding or
investigation pending or, to the knowledge of such Party, threatened against
such Party in respect of the transactions contemplated by this Agreement and the
Transaction Agreements.

      (d)   Except as disclosed in any Transaction Agreement or the applicable
schedule thereto, no person has or will have, as a result of the transactions
contemplated by this Agreement, any right, interest or claim against or upon
such Party for any commission, fee or other compensation as a finder or broker
because of any act or omission by such Party.

      9.    Certain Notices. Each Party hereto shall provide prompt written
notice to each other Party upon obtaining actual knowledge of any of the
following:

      (a)   the occurrence of any event or circumstance that has or is
reasonably expected to have (i) a "Company Material Adverse Effect" as defined
in the Protek Agreement, (ii) a "Parent Material Adverse Effect" or "Daleen
Material Adverse Effect" as defined in the Daleen Agreement, or (ii) a "Material
Adverse Effect" on Newco as such terms are defined in the Investment Agreement;

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      (b)   the pendancy of, or a threat to bring, any litigation, the
existence, or the entry of a final and adverse judgment in respect, of which
would cause any of the conditions set forth in Article VII of the Daleen
Agreement, Sections 8 and 9 of the Protek Agreement and Section 6 of the
Investment Agreement to fail to be satisfied if not cured prior to the date of
determination of satisfaction of such conditions;

      (c)   any material breach by such Party or another Party of any of the
covenants and agreements set forth in the Transaction Agreements or this
Agreement; and

      (d)   any event or occurrence which in such Party's opinion is reasonably
likely to result in any of the conditions set forth in Article VII of the Daleen
Agreement, Sections 8 and 9 of the Protek Agreement and Section 6 of the
Investment Agreement not being capable of being satisfied on or before September
30, 2004.

      10.   Certain Fees. (a) General. Terms used in this Section 10 without
definition have the meanings given to them in the Daleen Agreement.

      (b)   In the event (i) Daleen shall have terminated the Daleen Agreement
pursuant to Section 8.01(g) thereof or (ii) Parent shall have terminated the
Daleen Agreement pursuant to Section 8.01(f) thereof and either (1) the board of
directors of Daleen (or any committee thereof) shall have recommended to the
stockholders of Daleen a Competing Transaction or (2) Daleen enters into or
approves a definitive agreement with respect to, or consummates, a Competing
Transaction with any person (other than Parent, Merger Sub or their respective
affiliates) within twelve (12) months following such termination, then, in any
such case, Daleen shall promptly (and, in any event, within three (3) business
days after (x) termination by Daleen pursuant to clause (i) and (y) the later of
such termination or the consummation of such Competing Transaction pursuant to
clause (ii)), pay to the Quadrangle Entities (or to such entity(ies) as the
Quadrangle Entities may jointly designate in writing) their pro rata shares of
an aggregate one-time termination fee of $500,000 (the "Quadrangle Termination
Fee"). The Quadrangle Termination Fee shall be payable by wire transfer of
immediately available funds.

      (c)   Daleen shall pay Quadrangle Entities (or to such entity(ies) as the
Quadrangle Entities may jointly designate in writing) their pro rata shares of
an aggregate fee equal to the Transaction Expenses of the Quadrangle Entities
upon the termination of the Daleen Agreement pursuant to Section 8.01 thereof
(but excluding any termination thereof resulting from the covenants of the
Parties under Section 3 of this Agreement that arises from a breach by any
Quadrangle Entity of any of its representations, warranties, covenants or
agreements in the Investment Agreement). "Transaction Expenses" shall mean, in
respect of any given party, that party's reasonable documented out-of-pocket
fees, costs and expenses (including travel expenses and legal, accounting,
financial advisor and other consultant fees and expenses) incurred in connection
with this Agreement and the transactions contemplated by this Agreement,
including the preparation, execution and delivery of this Agreement and such
party's compliance with this Agreement, whether or not the transactions
contemplated hereby shall be consummated.

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      (d)   Daleen shall pay to Protek a fee equal to Protek's Transaction
Expenses upon the termination of the Daleen Agreement pursuant to Sections 8.01
(f) or (g) thereof, provided (i) that Protek shall not have been in breach of
any representation, warranty, covenant or agreement in the Protek Agreement at
the time of such termination that would give rise to a claim for indemnification
thereunder, and (ii) that no "Company Material Adverse Effect," as defined in
the Protek Agreement, shall exist at the time of such termination, and provided,
further, that such payment of Transaction Expenses shall be made first by offset
against the principal amount and accrued but unpaid interest owed to Daleen
under the Protek Bridge Facility (as defined in the Protek Agreement).

      (e)   Any payment required to be made pursuant to this Section 10 shall be
made as promptly as practicable but, in the case of paragraphs (c) and (d), not
later than five (5) business days after the final determination by the
Quadrangle Entities or Protek respectively of such amount and shall (subject to
the second proviso of paragraph (d) immediately preceding) be made by wire
transfer of immediately available funds to an account designated in writing by
the Quadrangle Entities or Protek, as the case may be.

      11.   No Publicity. No Party hereto shall issue any press release or make
any public announcement concerning this Agreement or the Transaction Agreements,
nor any transaction contemplated hereby or thereby, without the prior written
consent of each other Party hereto, which they may withhold in their reasonable
discretion (it being acknowledged and agreed that such discretion in approval
may reasonably include the effects of any such publicity on Daleen, including
the effects of the requirements of U.S. Federal securities laws and the costs
and administrative inconvenience which might be imposed by requiring parallel
announcements by Daleen). It is acknowledged and agreed that Daleen will
publicly announce the execution of this Agreement, the Protek Agreement, the
Daleen Agreement and the Investment Agreement, and will make such other public
filings in respect thereof and of the transactions contemplated hereby and
thereby as are required by law or are necessary or appropriate in order to
effect the transactions contemplated hereby and thereby.

      12.   Miscellaneous. This Agreement is governed by New York law without
regard to principles of conflict of law. Together with the Transaction
Agreements, this Agreement constitutes the entire agreement of the Parties in
respect of the subject matter of this Agreement and may only be amended in
writing by a document signed by all the Parties. This Agreement may be signed in
counterparts.

[Remainder of page intentionally left blank; counterpart signature pages follow]

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      The undersigned have executed this Agreement, intending to be bound
hereby, as of the date first set forth above.

                                 QUADRANGLE CAPITAL PARTNERS LP
                                   By: Quadrangle GP Investors LP, its General
                                       Partner
                                       By: Quadrangle GP Investors LLC, its
                                           General Partner

                                           By: /s/ M. Huber
                                               ---------------------------------
                                                Name: Michael Huber
                                                Title: Managing Principal

                                 QUADRANGLE SELECT PARTNERS LP
                                   By: Quadrangle GP Investors LP, its General
                                       Partner
                                       By: Quadrangle GP Investors LLC, its
                                           General Partner

                                           By: /s/ M. Huber
                                               ---------------------------------
                                                Name: Michael Huber
                                                Title: Managing Principal

                                 QUADRANGLE CAPITAL PARTNERS-A LP
                                   By: Quadrangle GP Investors LP, its General
                                       Partner
                                       By: Quadrangle GP Investors LLC, its
                                           General Partner

                                           By: /s/ M. Huber
                                               ---------------------------------
                                                Name: Michael Huber
                                                Title: Managing Principal

                                 Address for Notices for above signatories:

Counterpart Signature Page to Transaction Support Agreement

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                     Quadrangle Group LLC
                     375 Park Avenue
                     New York, New York 10152
                     Attention: Chief Financial Officer
                     Facsimile number: (212) 418-1701
                     Electronic mail address: michael.huber@quadranglegroup.com

                     with a copy (which shall not constitute
                     notice) to:

                     Weil, Gotshal & Manges LLP
                     100 Federal Street
                     Boston, MA 02110
                     Attention: James Westra, Esq.
                     Facsimile number:  (617) 772-8333
                     Electronic mail address: james.westra@weil.com

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         The undersigned have executed this Agreement, intending to be bound
hereby, as of the date first set forth above.

                               DALEEN TECHNOLOGIES, INC.

                               By: /s/ Gordon Quick
                                   ---------------------------------------------
                               Name: Gordon Quick
                               Title: President and Chief Executive Officer

                               DALEEN HOLDINGS, INC.

                               By: /s/ Gordon Quick
                                   ---------------------------------------------
                               Name: Gordon Quick
                               Title: Chief Executive Officer

                               Address for Notices for above signatories:

                               Daleen Technologies Inc.
                               902 Clint Moore Road, Suite 230
                               Boca Raton, FL  33489
                               Attention:  Director of Legal Affairs
                               Facsimile number:  (561) 981-1106
                               Electronic mail address:  dlandry@daleen.com

                               with a copy (which shall not constitute
                               notice) to:

                               Kirkpatrick & Lockhart LLP
                               535 Smithfield Street
                               Pittsburgh, PA 15222
                               Attention: Robert P. Zinn, Esq.
                               Facsimile number: (412) 355-6501
                               Electronic mail address: rzinn@kl.com

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      The undersigned have executed this Agreement, intending to be bound
hereby, as of the date first set forth above.

                                   BEHRMAN CAPITAL II, L.P.

                                   By : Behrman Brothers, LLC, its
                                   General Partner

                                   By: /s/ Grant Behrman
                                       ----------------------------------------
                                   Name: Grant Behrman
                                   Title: Managing Member

                                   STRATEGIC ENTREPRENEUR
                                   FUND II, L.P.

                                   By: /s/ Grant Behrman
                                        ---------------------------------------
                                   Name: Grant Behrman
                                   Title: General Partner

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      The undersigned have executed this Agreement, intending to be bound
hereby, as of the date first set forth above.

                                   PROTEK TELECOMMUNICATIONS SOLUTIONS LTD.

                                   By: /s/ P.A. Beaumont
                                       ----------------------------------------
                                   Name: P.A. Beaumont
                                   Title: CEO

                                   PAUL A. BEAUMONT

                                   /s/ P.A. Beaumont
                                   -----------------------------------

                                   GEOFF BUTCHER

                                   /s/ Geoff Butcher
                                   -----------------------------------

                                   IAN WATTERSON

                                   /s/ Ian Watterson
                                   -----------------------------------