Exhibit 99.7

                                 CARBOGEN AG
                             SUBSIDIARY GUARANTY

FOR VALUE RECEIVED, Carbogen AG, a company limited by shares organized under
the laws of Switzerland (the "GUARANTOR"), hereby irrevocably and
unconditionally guarantees, for the benefit of the Collateral Agent and the
holders of Notes (as hereinafter defined), as primary obligor and not merely
as surety, the full and punctual payment when due, subject to any applicable
grace period (whether at stated maturity, upon declaration of acceleration,
upon call for redemption, or otherwise), of all Guarantied Obligations (as
hereinafter defined) (including amounts that would become due but for the
operation of the automatic stay under any bankruptcy, insolvency or similar
law). Upon failure by the Issuer to pay punctually any such amount, the
Guarantor shall forthwith pay the amount not so paid.

Notwithstanding anything agreed in this Guaranty, this Guaranty (as the same
may be subsequently amended or novated), including the obligation of the
Guarantor as a Remaining Guarantor (as defined below):

(a) is limited to the maximum amount of the Guarantor's profits and reserves
which are available for distribution as dividends in accordance with
Articles 671, 671a to 673 and 675 of the Swiss Code of Obligations (the
"AVAILABLE AMOUNT") at the time that the Guarantor is required to make a
payment. Promptly after having been requested to make a payment under this
Guaranty, the Guarantor shall

         (i) use its best efforts to ensure that, if so requested by the
Collateral Agent or Requisite Noteholders, a meeting of its general assembly
of shareholders is duly held, within 30 Business Days the latest following
such request, to approve or confirm, as the case may be, the requested
payment up to the Available Amount; and

         (ii) pay promptly the Available Amount (plus the Swiss Withholding
Tax (if any) in accordance with paragraph (b) below),

it being understood that the said shareholders' resolution (if any) may be
requested by the Collateral Agent or Requisite Noteholders to be taken prior
to or following the payment by the Guarantor of the amount requested by the
Collateral Agent or Requisite Noteholders under this Guaranty.

(b) In relation to this Guaranty, the Guarantor shall, if and to the extent
required by applicable law in force at the relevant time, subject to any
applicable double taxation treaty, pay any Swiss withholding tax (the "SWISS
WITHHOLDING TAX"), at the rate of 35 per cent (or such other then applicable
rate) from any payment under this Guaranty and pay such Swiss Withholding
Tax to the Swiss Federal tax administration and, with respect to such
payments made, shall not be obliged to gross-up and indemnify the Collateral
Agent and the Noteholder even if such gross-up or indemnification is
generally provided for in the Terms and Conditions of Notes and/or in this
Guaranty.

(c) The Guarantor shall use its best efforts to ensure that its direct
parent company (or, if appropriate, any of its affiliate companies) will
take all steps necessary

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         (i) to obtain without delay a full or partial refund of the said
withholding tax payment, if and to the extent permissible under the
applicable provisions of the relevant double taxation treaty; and

         (ii) to make sure that the party receiving such refund (if any)
will pay such amount to the Collateral Agent, which payment shall be
accounted as a payment by the Guarantor under this Guaranty.

For purposes hereof, those certain (euro)200,000,000 6.25 percent Notes due
2005 (the "ORIGINAL NOTES"), of Solutia Europe SA/NV a company limited by
shares organized under the laws of Belgium (the "ISSUER"), including the
terms and conditions affixed thereto and incorporated by reference therein,
as amended and restated by those certain (euro)200,000,000 10.00 percent
Notes due 2008 of the Issuer, including the terms and conditions affixed
thereto and incorporated by reference therein (the terms and conditions of
notes, as amended, modified or supplemented from time to time, including all
exhibits and schedules thereto, the "TERMS AND CONDITIONS OF NOTES") and as
amended, modified, supplemented or replaced from time to time, including all
exhibits and schedules thereto, shall be referred to as the "NOTES". The
Notes amend and restate and evidence indebtedness previously evidenced by
the Original Notes and, in connection therewith, the Issuer has entered into
the Fiscal Agency Agreement dated 11 February 2004 with Kredietbank S.A.
Luxembourgeoise, as fiscal agent and paying agent (together with its
successors and assigns, the "FISCAL AGENT"), and KBC Bank NV, as the
principal paying agent (together with its successors and assigns, the
"PRINCIPAL PAYING AGENT") and the Agreement of Understanding and
Restructuring dated 30 January 2004 (as amended from time to time, the
"AGREEMENT OF UNDERSTANDING") with the Noteholders party thereto. All terms
not otherwise defined herein shall have the meanings set forth in the Terms
and Conditions of Notes.

For purposes hereof, the "COLLATERAL AGENT" refers to KBC BANK NV, as
collateral agent (together with its successors and assigns, the "COLLATERAL
AGENT"), appointed pursuant to the Collateral Agency Agreement dated 11
February 2004 (as it may be amended from time to time, the "COLLATERAL
AGENCY AGREEMENT") among the Issuer, the Subsidiary Guarantors party
thereto, the Collateral Agent and the Noteholders party thereto.

The term "GUARANTIED OBLIGATIONS" is used herein in its most comprehensive
sense and includes any and all Obligations (as defined in the Terms and
Conditions of Notes) of the Issuer to the Collateral Agent or any of the
Noteholders, including all obligations of the Issuer in respect of the
principal of, and interest on, the Notes and all other obligations of the
Issuer under or evidenced by the Notes, the Fiscal Agency Agreement, the
Collateral Agency Agreement and the other Credit Documents to which the
Issuer is party, including all costs, expenses (including, without
limitation, legal fees and expenses of counsel and allocated costs of
internal counsel), indemnities and liabilities of whatsoever nature, now or
hereafter made, incurred or created, whether absolute or contingent,
liquidated or unliquidated, whether due or not due, and however arising
under or in connection with the Notes, this Guaranty, the Fiscal Agency
Agreement, the Collateral Agency Agreement and the other Credit Documents,
including those arising under successive transactions under the Credit
Documents which shall either continue the Obligations of the Issuer or from
time to time renew them after they have been satisfied.

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Any interest on any portion of the Guarantied Obligations that accrues after
the commencement of any proceeding, voluntary or involuntary, involving the
bankruptcy, insolvency, receivership, reorganization, liquidation or
arrangement of the Issuer (or, if interest on any portion of the Guarantied
Obligations ceases to accrue by operation of law by reason of the
commencement of said proceeding, such interest as would have accrued on such
portion of the Guarantied Obligations if said proceeding had not been
commenced) shall be included in the Guarantied Obligations because it is the
intention that the Guarantied Obligations should be determined without
regard to any rule of law or order that may relieve Issuer of any portion of
such Guarantied Obligations.

The Collateral Agent or any Noteholder may from time to time, without notice
or demand and without affecting the validity or enforceability of this
Guaranty or giving rise to any limitation (other than the limitations set
forth in this Guaranty), impairment or discharge of Guarantor's liability
hereunder, (a) renew, extend, accelerate or otherwise change the time,
place, manner or terms of payment of the Guarantied Obligations, (b) settle,
compromise, release or discharge, or accept or refuse any offer of
performance with respect to, or substitutions for, the Guarantied
Obligations or any agreement relating thereto and/or subordinate the payment
of the same to the payment of any other obligations, (c) request and accept
other guaranties of the Guarantied Obligations and take and hold security
for the payment of this Guaranty or the Guarantied Obligations, (d) release,
exchange, compromise, subordinate or modify, with or without consideration,
any security for payment of the Guarantied Obligations, any other guaranties
of the Guarantied Obligations, or any other obligation of any Person with
respect to the Guarantied Obligations, (e) enforce and apply any security
now or hereafter held by or for the benefit of the Collateral Agent or any
Noteholder in respect of this Guaranty or the Guarantied Obligations and
direct the order or manner of sale thereof, or exercise any other right or
remedy that the Collateral Agent or the Noteholder, or any of them, may have
against any such security, as the Collateral Agent or any Noteholder in its
discretion may determine, including foreclosure on any such security
pursuant to one or more judicial or nonjudicial sales, whether or not every
aspect of any such sale is commercially reasonable, and (f) exercise any
other rights available to the Collateral Agent or the other Noteholders, or
any of them, under the Credit Document, at law or in equity.

The obligations of the Guarantor hereunder shall be unconditional and
absolute and, without limiting the generality of the foregoing, shall not be
released, discharged or otherwise affected by:

(a)     any extension, renewal, settlement, compromise, waiver or release in
        respect of any obligation of the Issuer, any other Credit Party or
        any other Person under the Notes or any other Credit Document or
        other agreement or instrument by the Collateral Agent, any
        Noteholder or any other Person or by operation of law;

(b)     any invalidity, irregularity, illegality or unenforceability of the
        Notes or any other Credit Document, or any provision of applicable
        law or regulation purporting to prohibit the payment of the
        principal of or interest on the Notes or any other Credit Document
        or any other amounts payable under the Notes;

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(c)     the existence of any claim, set-off or other rights that the
        Guarantor may have at any time against the Issuer, any other Credit
        Party or any other Person, whether or not arising in connection with
        this Subsidiary Guaranty, the Notes or any other Credit Document or
        otherwise; or

(d)     any other act or omission to act or delay of any kind by the Issuer,
        the Guarantor, and other Credit Party, the Collateral Agent, any
        Noteholders or any other Person or any other circumstance whatsoever
        that might, but for the provisions of this paragraph, constitute a
        legal or equitable discharge of the Guarantor's obligations under
        this Subsidiary Guaranty or any other Credit Document.

The Guarantor hereby waives notice of acceptance of this Guaranty or any
other Credit Document and also presentment, demand, protest and notice of
dishonor, and promptness in commencing suit against the Issuer or any other
Credit Party and/or in giving any notice to or of making any claim or demand
hereunder or under any other Credit Document upon the Guarantor or any other
Person. No failure or delay by the Collateral Agent in exercising any right,
power or privilege under this Guaranty or under any other Credit Document
shall operate as a waiver thereof nor shall any single or partial exercise
thereof preclude any other or further exercise thereof or the exercise of
any other right, power or privilege.

This Guaranty is a guarantee of payment and not of collection, and the
Guarantor hereby agrees that the obligations under this Guaranty are
independent of the obligations of the Issuer or any other Credit Party and
that a separate action may be brought and prosecuted against the Guarantor
whether or not action is brought against the Issuer or any other Credit
Party or whether or not the Issuer or any other Credit Party is joined in
such action.

The Guarantor's obligations under this Guaranty and the other Credit
Documents shall remain in full force and effect until the principal of, and
interest on, the Notes and all other amounts payable by the Issuer under the
Notes and payable by the Guarantor under this Guaranty and all other
Guarantied Obligations shall have been paid in full. If at any time any
payment of the principal of, and interest on, the Notes or any other amount
payable by the Issuer under the Notes or any other Guarantied Obligation is
rescinded or must be otherwise restored or returned upon the insolvency,
bankruptcy or reorganization of the Issuer or any other Credit Party or
similar circumstance, the Guarantor's obligations under this Guaranty with
respect to such payment shall be reinstated as though such payment had been
due but not made at such time.

The Guarantor shall be subrogated to all rights of the Collateral Agent and
the Noteholders against the Issuer in respect of any amounts paid to the
Collateral Agent and the Noteholders by the Guarantor pursuant to the
provisions of this Guaranty; provided, however, until the Guarantied
Obligations shall have been paid in full, Guarantor shall withhold exercise
of (a) any claim, right or remedy, direct or indirect, that Guarantor now
has or may hereafter have against the Issuer or any of its assets in
connection with this Guaranty or the performance by Guarantor of its
obligations hereunder, in each case whether such claim, right or remedy
arises in equity, under contract, by statute, under common law or otherwise
and including without limitation (i) any right of subrogation, reimbursement
or indemnification that Guarantor now has or may hereafter have against the
Issuer, (ii) any right to enforce, or to participate in, any claim, right or
remedy that the Collateral Agent or any Noteholder now has or may hereafter
have against the

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Issuer, and (iii) any benefit of, and any right to participate in, any
collateral or security now or hereafter held by the Collateral Agent or any
Noteholder and (b) any right of contribution Guarantor now has or may
hereafter have against any other guarantor of any of the Guarantied
Obligations. Guarantor further agrees that, to the extent the agreement to
withhold the exercise of its rights of subrogation, reimbursement,
indemnification and contribution as set forth herein is found by a court of
competent jurisdiction to be void or voidable for any reason, any rights of
subrogation, reimbursement or indemnification Guarantor may have against the
Issuer or against any collateral or security, and any rights of contribution
Guarantor may have against any such other guarantor, shall be junior and
subordinate to any rights of the Collateral Agent and any Noteholders may
have against the Issuer, to all right, title and interest the Collateral
Agent and any Noteholders may have in any such collateral or security, and
to any right the Collateral Agent and any Noteholders may have against such
other guarantor.

Any indebtedness of the Issuer or any other Credit Party now or hereafter
held by Guarantor is subordinated in right of payment to the Guarantied
Obligations, and any such indebtedness of such Person to Guarantor collected
or received by Guarantor after an Event of Default has occurred and is
continuing, and any amount paid to Guarantor on account of any subrogation,
reimbursement, indemnification or contribution rights referred to in the
preceding paragraph when all Guarantied Obligations have not been paid in
full, shall be held in trust for the Collateral Agent on behalf of the
Noteholders and shall forthwith be paid over to the Collateral Agent for the
benefit of the Noteholders to be credited and applied against the Guarantied
Obligations.

In order to provide for just and equitable contribution among the Guarantor
and the other Subsidiary Guarantors party to the Agreement of Understanding
(for purposes of this paragraph individually a "GUARANTOR" and collectively,
the "GUARANTORS"), in connection with the execution of their respective
Subsidiary Guaranties, the Guarantors have agreed among themselves that if
any such Guarantor satisfies some or all of the Obligations (a "FUNDING
GUARANTOR"), the Funding Guarantor shall be entitled to contribution from
the other Guarantors that have positive Maximum Net Worth (as defined below)
for all payments made by the Funding Guarantor in satisfying the Guarantied
Obligations, so that each Guarantor that remains obligated under this
Guaranty or any other guaranty for the Guarantied Obligations at the time
that a Funding Guarantor makes such payment (a "REMAINING GUARANTOR") and
has a positive Maximum Net Worth shall bear a portion of such payment equal
to the percentage that such Remaining Guarantor's Maximum Net Worth bears to
the aggregate Maximum Net Worth of all Remaining Guarantors that have
positive Maximum Net Worth. As used herein, "NET WORTH" means, with respect
to any Guarantor, the amount, as of the respective date of calculation, by
which the sum of a Person's assets (including subrogation, indemnity,
contribution, reimbursement and similar rights that such Guarantor may
have), determined on the basis of a "fair valuation" or their "fair saleable
value" (whichever is the applicable test under Section 548 and other
relevant provisions of the Bankruptcy Code and the relevant state fraudulent
conveyance or transfer laws), is greater than the amount that will be
required to pay all of such Person's debts, in each case matured or
unmatured, contingent or otherwise, as of the date of calculation, but
excluding liabilities arising under this Guaranty or any other guaranty for
the Obligations and excluding, to the maximum extent permitted by applicable
law with the objective of avoiding rendering such Person insolvent,
liabilities subordinated to the Obligations arising out of loans or advances
made to such Person by any other Person. "MAXIMUM NET

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WORTH" means, with respect to any Guarantor, the greatest of the Net Worths
of such Guarantor calculated as of the following dates: (A) the date on
which such Person becomes a Guarantor, and (B) the date on which such
Guarantor expressly reaffirms this Guaranty or the other guaranty to which
it is a party. The meaning of the terms "FAIR VALUATION" and "FAIR SALEABLE
VALUE" and the calculation of assets and liabilities shall be determined and
made in accordance with the relevant provisions of the Bankruptcy Code and
applicable state fraudulent conveyance or transfer laws. The rights and
obligations of each Guarantor established pursuant to this paragraph (and
the related paragraphs of the other Subsidiary Guaranties) shall be subject
to the restrictions and limitations benefiting the Collateral Agent and the
Noteholders set forth in the preceding two paragraphs.

Guarantor agrees to pay, or cause to be paid, on demand, and to save the
Collateral Agent harmless against liability for, (i) any and all costs and
expenses (including fees, costs of settlement and disbursements of counsel
and allocated costs of internal counsel) incurred or expended by the
Collateral Agent in connection with the enforcement of or preservation of
any rights under this Guaranty and (ii) any and all costs and expenses
(including those arising from rights of indemnification) required to be paid
by Guarantor under the provisions of any other Credit Document to which it
is party.

Any monies paid by the Guarantor to the Principal Paying Agent or a Paying
Agent for payment of Guarantied Obligations which remain unclaimed for two
years after such monies have become due and payable will be repaid to the
Guarantor and the beneficiaries of this Guaranty may thereafter look only to
the Issuer and the other Credit Parties, as the case may be, for payment
thereof.

All of the provisions of this Guaranty shall be binding upon the Guarantor
and its successors, permitted transferees and assigns and inure to the
benefit of, and be enforceable by, the Collateral Agent and its successors,
transferees and assigns and Requisite Noteholders as defined and provided in
the Collateral Agency Agreement; it being understood that the rights and
remedies under this Guaranty shall not be enforceable by an individual
holder of a legal or beneficial interest of a Note unless such holder is
acting with the instructions or at the request of Requisite Noteholders.

The Guarantor hereby further agrees that any amounts to be paid under this
Guaranty shall be paid without deduction or withholding for or on account of
any present or future taxes, assessments, duties or governmental charges of
any nature whatsoever imposed, levied or collected by or in or on behalf of
the United States or any other Governmental Authority or by or on behalf of
any political subdivision or authority therein having power to tax, unless
such deduction or withholding is required by law. In such event, the
Guarantor shall pay such additional amounts of principal and interest and
other amounts as may be necessary in order that the net amounts received by
the Collateral Agent and the Noteholders, as the case may be, after such
deduction or withholding shall not be less than the respective amounts of
principal and interest and other amounts which would have been received had
no such deduction or withholding been required. No such additional amounts
shall, however, be payable with respect to:

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(a) any Note or Coupon presented for payment by, or on behalf of, a holder
who is liable for such taxes or duties in respect of such Note or Coupon by
reason of his having some connection with the Kingdom of Belgium or the
United States, other than the mere holding of such Note or Coupon or the
receipt of payments in respect thereto; or

(b) any Note or Coupon presented for payment more than 30 days after the
Relevant Date (as defined below) except to the extent that the holder
thereof would have been entitled to such additional amounts on presenting
the same for payment on such thirtieth day; or

(c) any estate, inheritance, gift, sales, transfer, personal property or any
similar tax, assessment or other governmental charge; or

(d) any tax, assessment or other governmental charge which is payable
otherwise than by withholding from payment of principal or interest, if any,
with respect to such Note or Coupon; or

(e) any tax, duty, levy, assessment or other governmental charge that would
not have been imposed but for the fact that such Noteholder or Couponholder
presented (if presentation is required) such Note or Coupon for payment in
the applicable taxing jurisdiction, unless such Note or Coupon could not
have been presented for payment elsewhere; or

(f) any tax, assessment or other governmental charge that is imposed or
withheld by reason of the failure to comply by the Noteholder or
Couponholder or the beneficial owner of the Note or Coupon with a request of
the Issuer or the Guarantor (a) to provide information concerning the
nationality, residence or identity of the Noteholder or Couponholder or such
beneficial owner or (b) to make any declaration or other similar claim or
satisfy any information or reporting requirements, which, in the case of (a)
or (b), is required or imposed by a statute, treaty, regulation or
administrative practice of the applicable taxing jurisdiction as a
precondition to exemption from all or part of such tax, assessment or other
governmental charge; or

(g) in relation to additional amounts in respect of taxes and duties imposed
or levied by the Kingdom of Belgium only to any holder who is not the sole
beneficial owner of such Note or Coupon to the extent that a beneficial
owner thereof, any Note or Coupon held by or on behalf of a holder who, at
the time of issue of the Notes, was not an eligible investor within the
meaning of Article 4 of the Royal Decree on 26 May, 1994 on the deduction of
withholding tax or who was an eligible investor at the time of issue of the
Notes but, for reasons within the holder's control, ceased to be an eligible
investor or, at any relevant time on or after the issue of the Notes,
otherwise failed to meet any other condition for the exemption of Belgian
withholding tax pursuant to the law of 6 August, 1993 relating to certain
securities; or

(h) any combination of (a) to (g);

nor in any case, with respect to the Issuer or the Guarantor shall
additional amounts be paid to any holder who is not the sole beneficial
owner of such Note or Coupon to the extent that a beneficial owner thereof
would not have been entitled to the additional amounts had such beneficial
owner been the holder of such Note or Coupon.

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As used herein, "Relevant Date" means whichever is the later of (i) the date
on which such payment first becomes due and (ii) if the full amount of the
moneys payable has not been made available to the Fiscal Agent on or prior
to such date, the date on which, the full amount of such moneys having been
made available, notice to that effect shall have been given to the
Noteholders in accordance with the notice provisions described in the Terms
and Conditions of the Notes.

The obligation of the Guarantor to make payments of principal of, or
interest on, or other amount due under this Guaranty shall not be discharged
or satisfied by any tender or recovery pursuant to any judgment expressed in
or converted into any currency other than the currency specified in the
Notes except to the extent that such tender or recovery shall result in the
effective receipt by the Collateral Agent or the relevant Noteholder of the
full amount of the currency specified in the Notes, and accordingly the
primary obligation of the Guarantor shall be enforceable as an alternative
or additional cause of action for the purpose of recovery in the judgment
currency of the amount (if any) by which such effective receipt shall fall
short of the full amount of the currency specified in the Notes and shall
not be affected by a judgment being obtained for any other sum due under
this Guaranty.

THIS GUARANTY AND THE RIGHTS AND OBLIGATIONS OF GUARANTOR, THE COLLATERAL
AGENT AND THE OTHER NOTEHOLDERS HEREIN SHALL BE GOVERNED BY, AND SHALL BE
CONSTRUED AND ENFORCED IN ACCORDANCE WITH, THE INTERNAL LAWS OF THE STATE OF
NEW YORK (INCLUDING WITHOUT LIMITATION SECTION 5-1401 OF THE GENERAL
OBLIGATIONS LAW OF THE STATE OF NEW YORK), WITHOUT REGARD TO CONFLICTS OF
LAWS PRINCIPLES.

The Guarantor hereby agrees, for the benefit of the Collateral Agent, and
the holders of the Notes (i) to be bound by the covenants in Sections 7 and
8 of the Terms and Conditions of the Notes that are applicable to such
Guarantor as a Subsidiary of the Issuer, and (ii) to take any and all
actions (or omit to take any and all actions) in order to not cause a
Default or an Event of Default by Guarantor under such covenants in the
Terms and Conditions of the Notes.

The Guarantor hereby represents and warrants to the Collateral Agent that
the statements set forth in Section IV to the Agreement of Understanding
applicable to the Guarantor are true, correct and complete on and as of the
date of this Subsidiary Guaranty.

The Guarantor hereby irrevocably submits to the non-exclusive jurisdiction
of any state or United States Federal court sitting in the Borough of
Manhattan, New York City, State of New York and of any Belgian court
sitting in Brussels over any suit, action or proceeding arising out of or
relating to this Guaranty or any other Credit Document to which it is a
party. The Guarantor irrevocably waives, to the fullest extent permitted by
law, any objection which it may have to the laying of the venue of any such
suit, action or proceeding brought in such a court and any claim that any
such suit, action or proceeding brought in such a court has been brought in
an inconvenient forum. As long as any of the Guarantied Obligations remain
outstanding, the Guarantor will at all times have an authorized agent for
service of process in New York City and in Belgium, upon whom process may
be served in any suit, action or proceeding arising out of or relating to
this Guaranty or any other Credit Document to which it is a party. Service
of

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process upon such agent and written notice of such service mailed or
delivered to the Guarantor shall to the extent permitted by law be deemed in
every respect effective service of process upon the Guarantor in any such
suit, action or proceeding. The Guarantor hereby appoints CT Corporation
System, 111 Eighth Avenue, New York, New York 10011 and the Issuer as its
agents for such purpose, and covenants and agrees that (i) service of
process in any such suit, action or proceeding may be made upon it at the
specified office of any such agent (or such other address or at the office
of any other authorized agent which the Guarantor may designate by written
notice to the Collateral Agent) and (ii) prior to any termination of any
such agency for any reason, it will so appoint a successor thereto as agent
hereunder.

GUARANTOR AND, BY ITS ACCEPTANCE OF THE BENEFITS HEREOF, COLLATERAL AGENT ON
BEHALF OF ITSELF AND EACH NOTEHOLDER, EACH AGREES TO WAIVE ITS RESPECTIVE
RIGHTS TO A JURY TRIAL OF ANY CLAIM OR CAUSE OF ACTION BASED UPON OR ARISING
OUT OF THIS GUARANTY. THE SCOPE OF THIS WAIVER IS INTENDED TO BE
ALL-ENCOMPASSING OF ANY AND ALL DISPUTES THAT MAY BE FILED IN ANY COURT AND
THAT RELATE TO THE SUBJECT MATTER OF THIS TRANSACTION, INCLUDING WITHOUT
LIMITATION CONTRACT CLAIMS, TORT CLAIMS, BREACH OF DUTY CLAIMS AND ALL OTHER
COMMON LAW AND STATUTORY CLAIMS. GUARANTOR AND, BY ITS ACCEPTANCE OF THE
BENEFITS HEREOF, COLLATERAL AGENT ON BEHALF OF ITSELF AND EACH NOTEHOLDER,
EACH (I) ACKNOWLEDGES THAT THIS WAIVER IS A MATERIAL INDUCEMENT TO ENTER
INTO A BUSINESS RELATIONSHIP, THAT GUARANTOR AND COLLATERAL AGENT HAVE
ALREADY RELIED ON THIS WAIVER IN ENTERING INTO THIS GUARANTY OR ACCEPTING
THE BENEFITS THEREOF, AS THE CASE MAY BE, AND THAT EACH WILL CONTINUE TO
RELY ON THIS WAIVER IN THEIR RELATED FUTURE DEALINGS, AND (II) FURTHER
WARRANTS AND REPRESENTS THAT EACH HAS REVIEWED THIS WAIVER WITH ITS LEGAL
COUNSEL AND THAT EACH KNOWINGLY AND VOLUNTARILY WAIVES ITS JURY TRIAL RIGHTS
FOLLOWING CONSULTATION WITH LEGAL COUNSEL. THIS WAIVER IS IRREVOCABLE,
MEANING THAT IT MAY NOT BE MODIFIED EITHER ORALLY OR IN WRITING, AND THIS
WAIVER SHALL APPLY TO ANY SUBSEQUENT AMENDMENTS, RENEWALS, SUPPLEMENTS OR
MODIFICATIONS OF THIS GUARANTY. In the event of litigation, this Guaranty
may be filed as a written consent to a trial by the court.

If one or more provisions contained in this Subsidiary Guaranty shall be
invalid, illegal or unenforceable in any respect under any applicable law,
the validity, legality, or enforceability of the remaining provisions shall
not in any way be affected or impaired.

This Guaranty may be executed in any number of counterparts and by the
different parties hereto in separate counterparts, each of which when so
executed and delivered shall be deemed to be an original for all purposes;
but all such counterparts together shall constitute but one and the same
instrument.

No amendment, modification, termination or waiver of any provision of this
Guaranty, and no consent to any departure by Guarantor therefrom, shall in
any event be effective without the

                                     9




written concurrence of Collateral Agent and, in the case of any such
amendment or modification, Guarantor. Any such waiver or consent shall be
effective only in the specific instance and for the specific purpose for
which it was given.

The Collateral Agent has been appointed to act as Collateral Agent pursuant
to the Collateral Agency Agreement. The Collateral Agent shall be obligated,
and shall have the right hereunder, to make demands, to give notices, to
exercise or refrain from exercising any rights, and to take or refrain from
taking any action, solely in accordance with this Guaranty and the
Collateral Agency Agreement.

Collateral Agent shall at all times be the same Person that is Collateral
Agent under the Collateral Agency Agreement. Written notice of resignation
by Collateral Agent pursuant to Section 7 of the Collateral Agency Agreement
shall also constitute notice of resignation as Collateral Agent under this
Guaranty and the other Credit Documents to which the Guarantor is party;
removal of Collateral Agent pursuant to Section 7 of the Collateral Agency
Agreement shall also constitute removal as Collateral Agent under this
Guaranty and the other Credit Documents to which the Guarantor is party; and
appointment of a successor Collateral Agent pursuant to Section 7 of the
Collateral Agency Agreement shall also constitute appointment of a successor
Collateral Agent under this Guaranty and the other Credit Documents to which
the Guarantor is party. Upon the acceptance of any appointment as Collateral
Agent under Section 7 of the Collateral Agency Agreement by a successor
Collateral Agent, that successor Collateral Agent shall thereupon succeed to
and become vested with all the rights, powers, privileges and duties of the
retiring or removed Collateral Agent under this Guaranty and the other
Credit Documents to which the Guarantor is party, and the retiring or
removed Collateral Agent under this Guaranty shall promptly (i) transfer to
such successor Collateral Agent all sums held hereunder, together with all
records and other documents necessary or appropriate in connection with the
performance of the duties of the successor Collateral Agent under this
Guaranty and the other Credit Documents to which the Guarantor is party, and
(ii) take such other actions as may be necessary or appropriate in
connection with the assignment to such successor Collateral Agent of the
rights created hereunder, whereupon such retiring or removed Collateral
Agent shall be discharged from its duties and obligations under this
Guaranty and other Credit Documents to which the Guarantor is party. After
any retiring or removed Collateral Agent's resignation or removal hereunder
as Collateral Agent, the provisions of this Guaranty and other Credit
Documents to which the Guarantor is party shall inure to its benefit as to
any actions taken or omitted to be taken by it under this Guaranty or the
other Credit Documents to which the Guarantor is party while it was
Collateral Agent hereunder.

All notices and other communications under this Guaranty shall be in writing
and shall be personally delivered or sent by prepaid courier, by overnight,
registered or certified mail (postage prepaid), or by prepaid telex,
telecopy or telegram, and shall be deemed given when received by the
intended recipient thereof. Unless otherwise specified in a notice given in
accordance with the foregoing provisions of this Section, all notices and
other communications shall be given to the parties hereto at their
respective addresses (or to their respective telex or telecopier numbers)
indicated in the Agreement of Understanding.

This Guaranty is executed in English only, and no translation thereof shall
be binding on the parties hereto or consulted in order to interpret this
Guaranty.


                                     10




IN WITNESS WHEREOF, the Guarantor and the Collateral Agent has caused this
Subsidiary Guaranty to be duly executed by its duly authorized officer.

                                CARBOGEN AG

                                By /s/ Kristel Deroover
                                   -----------------------------------------
                                         Name: Kristel Deroover
                                                ----------------------------
                                         Title: Attorney
                                                ----------------------------


                                KBC BANK NV

                                By /s/ Dirk De Bleser
                                   -----------------------------------------
                                         Name: Dirk De Bleser
                                                ----------------------------
                                         Title: Head Operations & Accounting
                                                ----------------------------
Dated: 11 February 2004



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