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                                                                    Exhibit 4.15

Certificate No:  107

WARRANT TO SUBSCRIBE FOR SHARES

GENTIA SOFTWARE PLC

(Incorporated under the Companies Act 1985 No 2857046)

Warrant to subscribe for 59,459 ordinary shares of 15 pence each

THIS IS TO CERTIFY that Banco Nominees (Guernsey) Limited of PO Box 208, Bermuda
House, St. Julian's Avenue, St. Peter Port, Guernsey GY1 3NF is the registered
holder of a warrant to subscribe for 59,459 ordinary shares of 15 pence each in
Gentia Software plc (the "Company") subject to the memorandum and articles of
association of the Company and otherwise on the terms and conditions set out
overleaf which provide, inter alia, for adjustment to the number of shares
subject to the Warrant and to the Warrant Price (as defined overleaf) in certain
circumstances.

EXECUTED as a deed by the Company on 9th December 1999.

SIGNED as a deed and DELIVERED by GENTIA SOFTWARE PLC acting by a Director and
the Secretary/two Directors:

/s/ Steve Fluin Director
---------------

/s/ Nicholas P.S. Bray Director/Secretary
----------------------

IMPORTANT

(1)      The Warrant evidenced by this Certificate is exercisable for a period
         of seven years after the date of this Certificate and thereafter up to
         and including 9th December 2006 by completion of the Notice of Exercise
         set out below and lodgement of this Certificate at the then registered
         office of the Company together with the appropriate payment.
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NOTICE OF EXERCISE

To the directors of Gentia Software plc

I/We hereby exercise my/our Warrant evidenced by this Certificate to subscribe
for ** Ordinary Shares of 15p each in your Company and attach a cheque for US$

Signed:

___________________________________________________________




We request that a certificate for the said Ordinary Shares and a balance
certificate in respect of the Warrant be sent by post to us at our risk at the
first address shown or to the agent lodging this Certificate.

Signed:

___________________________________________________________


----------
**       Please complete. If no number is inserted the Notice will be deemed to
         relate to all the shares subject to the Warrant.


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TERMS AND CONDITIONS

1.       In these terms and conditions:

         "Company" means Gentia Software plc (registered number 2857046);

         "Final Exercise Date" means the earlier of 9th December 2006 and the
         expiration of a notice given by the Company pursuant to paragraph 3
         below;

         "Ordinary Shares" means ordinary shares of 15p each in the capital of
         the Company;

         "Registered Holder" means Banco Nominees (Guernsey) Limited of PO Box
         208, Bermuda House, St. Julian's Avenue, St. Peter Port, Guernsey GY1
         3NF;

         "this Warrant" means the warrant, evidenced by this Certificate, to
         subscribe for the number of Ordinary Shares (subject to variation as
         specified in this Warrant) specified on the face of this Certificate;

         "Warrant Price" means the price per share at which the Registered
         Holder is entitled to subscribe for the Ordinary Shares which are
         subject to this Warrant.

2.       This Warrant is held subject to the memorandum and articles of
         association of the Company and otherwise on these terms and conditions
         which are binding upon the Company and the Registered Holder and all
         persons claiming through or under them respectively. This Warrant will
         be registered and the subscription rights represented thereby will be
         transferable.

3.       The Registered Holder shall have the right upon exercise of this
         Warrant to subscribe in cash for Ordinary Shares. This Warrant is
         exercisable by the Registered Holder in whole or in part at any time
         and from time to time during a period from the date of this Certificate
         up to and including 9th December 2006 PROVIDED THAT if at any time this
         Warrant has been exercised in respect of three fifths or more of the
         ordinary shares which are the subject of this Warrant the Company may
         by thirty days' written notice to the Registered Holder may require it
         to exercise this Warrant in respect of any remaining shares the subject
         thereof. At midnight on the said date or after the expiration of the
         said notice (whichever is earlier) this Warrant shall become null and
         void and of no effect.

4.       Subject as hereinafter mentioned, the Warrant Price is US$4.625 per
         Ordinary Share.


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5.       In order to exercise this Warrant the Notice of Exercise must be
         completed and signed by the Registered Holder and lodged at the then
         registered office of the Company together with a payment to the Company
         equal to the Warrant Price multiplied by the number of Ordinary Shares
         in respect of which this Warrant is exercised. Any Notice of Exercise
         shall be irrevocable without the written consent of the Company once it
         has been lodged.

6.       If this Warrant is exercised before the Final Exercise Date in respect
         of part only of the Ordinary Shares the subject of this Warrant, a
         certificate in respect of the balance will be issued by the Company to
         the Registered Holder.

7.       Ordinary Shares in respect of which this Warrant is exercised will be
         issued only to the Registered Holder.

8.       Ordinary Shares issued pursuant to the exercise of this Warrant will
         rank pari passu in all respects from the date of issue with the
         remaining Ordinary Shares then in issue except that they will not rank
         for dividends or other distributions declared, made or paid on or after
         the date of issue in respect of a financial year (as defined in Section
         742 of the Companies Act 1985) or other accounting reference period of
         the Company ending on or before the date of issue nor for dividends or
         other distributions declared, resolved upon or publicly announced
         before the date of exercise of this Warrant.

9.       Adjustment of subscription rights attached to this Warrant

         (a)      If, on a date (or by reference to a record date) on or before
                  the Final Exercise Date, the Company allots any fully paid
                  Ordinary Shares by way of capitalisation of profits or
                  reserves to holders of the Ordinary Shares or effects any
                  consolidation or sub-division of the Ordinary Shares on such a
                  date, the number and/or nominal value of Ordinary Shares to be
                  subscribed on any subsequent exercise of subscription rights
                  attached to this Warrant will as from such date (or record
                  date) be increased or, as the case may be, reduced in due
                  proportion and the Warrant Price will be adjusted accordingly.
                  On any such capitalisation, consolidation or sub-division the
                  auditors for the time being of the Company shall certify the
                  appropriate adjustments and, within twenty-eight days
                  thereafter, notice will be sent to the Registered Holder
                  together with a Warrant certificate in respect of any
                  additional Ordinary Shares for which the Registered Holder is
                  entitled to subscribe in consequence of such adjustments,
                  fractional entitlements being ignored.


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         (b)      If, on a date (or by reference to a record date) on or before
                  the Final Exercise Date the Company makes any offer or
                  invitation (whether by way of rights issue or otherwise but
                  not being an offer to which paragraph 10(b) below applies) to
                  the holders of the Ordinary Shares, or any offer or invitation
                  (not being an offer to which paragraph 10(c) below applies) is
                  made to such holders otherwise than by the Company, then the
                  Company shall, so far as it is able, procure that at the same
                  time the same offer or invitation is made to the Registered
                  Holder as if its subscription rights under this Warrant had
                  been exercisable and had been exercised on the day immediately
                  preceding such date (or record date) on the basis then
                  applicable.

         10.      So long as any subscription rights attached to this Warrant
                  remain exercisable, save with agreement or sanction pursuant
                  to paragraph 11 below:

         (a)      the Company shall:

                  (i)      keep available for issue sufficient authorised but
                           unissued share capital to satisfy in full all
                           subscription rights attached to this Warrant
                           remaining exercisable;

                  (ii)     not make any allotment of fully paid Ordinary Shares
                           by way of capitalisation of profits or reserves on or
                           before the Final Exercise Date unless at the date of
                           such allotment the directors have authority for the
                           purposes of section 80 of the Companies Act 1985 to
                           grant the additional rights to subscribe to which the
                           Registered Holder would by virtue of paragraph 9(a)
                           above be entitled in consequence of such
                           capitalisation; and

                  (iii)    not make any offer or invitation as is referred to in
                           paragraph 9(b) above to the holders of Ordinary
                           Shares unless:

                           (aa)     where such offer or invitation involves the
                                    allotment of relevant securities (as defined
                                    in section 80 of the Companies Act 1985) the
                                    directors shall have authority for the
                                    purposes of that section to allot any such
                                    securities as may require to be allotted to
                                    the Registered Holder in consequence of the
                                    Company making the same offer or invitation
                                    to the Registered Holder in accordance with
                                    paragraph 9(b) above; and


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                           (bb)     section 89(1) of such Act shall have been
                                    disapplied to the extent (if any) necessary
                                    to enable the Company to make such offer or
                                    invitation to the Registered Holder and to
                                    make any allotment pursuant thereto;

         (b)      if at any time before the Final Exercise Date an offer or
                  invitation is made by the Company to the holders of Ordinary
                  Shares for the purchase by the Company of any of its Ordinary
                  Shares, the Company shall simultaneously give notice thereof
                  to the Registered Holder and the Registered Holder shall be
                  entitled, at any time while such offer or invitation is open
                  for acceptance, to exercise its subscription rights under this
                  Warrant on the terms on which the same could have been
                  exercised (subject to any adjustment pursuant to paragraph
                  9(a) above) so as to take effect as if it had exercised such
                  rights on the day immediately preceding the record date for
                  such offer or invitation and the Company shall procure that
                  any such offer or invitation is extended to any Ordinary
                  Shares arising from such exercise;

         (c)      if at any time an offer is made to all the holders of Ordinary
                  Shares (or all such holders other than the offeror) to acquire
                  the whole or any part of the issued ordinary share capital of
                  the Company and the Company becomes aware that as a result of
                  such an offer the right to cast a majority of the votes which
                  may ordinarily be cast on a poll at a General Meeting of the
                  Company has or will become vested in the offeror, the Company
                  shall give notice to the Registered Holder of such vesting
                  within fourteen days of its becoming so aware, and the
                  Registered Holder shall be entitled, at any time within the
                  period of thirty days immediately following the date of such
                  notice but before the Final Exercise Date, to exercise its
                  subscription rights under this Warrant on the terms on which
                  the same are then exercisable (subject to any adjustment
                  pursuant to paragraph 9(a) above) so as to take effect as if
                  it had exercised its rights on the day immediately preceding
                  the record date for such offer, and the Company shall use its
                  best endeavours to ensure that such offer is extended to any
                  Ordinary Shares arising from such exercise (and the
                  publication of a scheme of arrangement under section 425 of
                  the Companies Act 1985 providing for the acquisition by any
                  person of the whole or any part of the issued Ordinary share
                  capital of the Company shall be deemed to be the making of an
                  offer for the purposes of this sub-paragraph (c));


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         (d)      if before the Final Exercise Date an order is made or an
                  effective resolution is passed for winding up the Company the
                  Registered Holder will (if, in such winding up and on the
                  basis that all subscription rights attached to this Warrant
                  then unexercised had been exercised in full and the
                  subscription moneys therefor had been received in full by the
                  Company there shall be a surplus available for distribution
                  amongst the holders of the Ordinary Shares which on such basis
                  would exceed in respect of each Ordinary Share a sum equal to
                  the Warrant Price) be treated as if immediately before the
                  date of such order or resolution its subscription rights under
                  this Warrant had been exercisable and had been exercised in
                  full, on the terms on which the same could then have been
                  exercised (subject to any adjustment pursuant to paragraph
                  9(a) above) so as to take effect as if it had exercised such
                  rights on the day immediately preceding the date of such order
                  or resolution and shall accordingly be entitled to receive out
                  of the assets available in the liquidation pari passu with the
                  holders of the Ordinary Shares such a sum as it would have
                  received had it been the holder of the Ordinary Shares to
                  which it would have become entitled by virtue of such
                  subscription after deducting a sum per Ordinary Share equal to
                  the Warrant Price; subject to the foregoing all subscription
                  rights shall lapse on liquidation of the Company.

11.      If any question shall arise in regard to the nature or extent of any
         adjustment to be made to the Warrant Price or the number of Ordinary
         Shares subject to this Warrant pursuant to any of the provisions of
         paragraph 9 above, the same shall be referred for determination either
         by some person, firm or company nominated jointly for such purpose by
         the Company and the Registered Holder or, failing agreement on such
         joint nomination, by a firm of Chartered Accountants to be nominated at
         the request of the Company or the Registered Holder by the President
         for the time being of the Institute of Chartered Accountants in England
         and Wales and so that any person, firm or company so nominated shall be
         deemed to be acting as an expert or experts and not as an arbitrator or
         arbitrators and his or their decision shall be binding on all
         concerned. The costs of such determination shall be divided equally
         between the Company and the Registered Holder.

12.      All or any of the rights for the time being attached to this Warrant
         may from time to time (whether or not the Company is being wound up) be
         altered or abrogated with the consent in writing both of the Company
         and of the Registered Holder.

13.      This Warrant is not transferable. If the Registered Holder purports to
         transfer this Warrant in whole or in part to any other person this
         Warrant shall cease to have effect and shall become null and void.


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