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                                                                    Exhibit 4.10

                                            [JAMES HARDIE LOGO]

                                            JAMES HARDIE INDUSTRIES NV

May 10, 2005

Mr. Benjamin Butterfield

Dear Ben,

We are excited to offer you an International Assignment as General Counsel of
James Hardie Industries NV located in Amsterdam, Netherlands for a minimum of
three (3) years. This assignment commences on or around May 23, 2005 or on the
date of your official relocation to Amsterdam. The term of this international
assignment may be extended by mutual agreement.

This letter sets forth the terms and conditions on which you are offered this
assignment and your continued employment with James Hardie Industries, NV
("JHINV" or "the Company").

GENERAL TERMS AND CONDITIONS:

LOCATION OF SERVICE:            This position will be located at JHI NV's office
                                in Amsterdam.

REPORTING RELATIONSHIP:         You will continue to report to Louis Gries, CEO
                                of JHI NV.

DUTIES:                         The duties of this position will be as set out
                                in a separate document. You are expected to
                                perform these duties to the best of your
                                abilities and to devote your full business time
                                and energy to the satisfactory performance of
                                these duties.

REMUNERATION:                   ANNUAL SALARY: Your annual base salary will
                                continue to be US $300,000, less applicable
                                withholding, and will be paid according to the
                                standard payroll schedule. This salary will be
                                reviewed in July of each year, starting July
                                2005 to determine if any adjustments are
                                required.

                                EXPATRIATE ALLOWANCE: On the basis that you will
                                be living away from your usual place of
                                residence, you will receive an expatriate
                                allowance of US $19,000 per year, this allowance
                                will be grossed up for taxes. This allowance
                                will be adjusted annually based on the amount of
                                time estimated to be spent in Amsterdam
                                (currently estimated at 75%) and the amount of
                                Goods and Services allowance provided by AIRINC
                                required to off-set the foreign exchange and
                                cost of living between California and Amsterdam.

                                Your remuneration relies on the fact that you
                                are living away from home and therefore you will
                                be required to sign a declaration to that effect
                                annually (see attached), which the company will
                                retain with its records.

PERFORMANCE BONUS:              You will continue to be eligible for
                                participation in the EP Incentive Plan in
                                accordance with the terms of the Plan. Effective
                                April 1, 2005, your annual target bonus payout
                                is 65% of your annual base salary, split 80%
                                based on company EP performance and 20% based on
                                your personal performance.

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                                                                    Exhibit 4.10

TAXATION ADVICE:                The Company will pay the costs of filing your US
                                and Netherlands income tax returns as a
                                consequence of your assignment to the
                                Netherlands. These returns will be prepared by
                                Ernst & Young.

VACATION AND HOME LEAVE:        ANNUAL VACATION: You will continue to accrue
                                vacation at your current rate. Accrued vacation
                                may be utilized during the assignment, with your
                                Manager's approval.

                                HOME LEAVE: During your assignment, the Company
                                will pay for business class airfare for you to
                                return to the United States twice per year.

CAR:                            JHINV will provide a fully maintained automobile
                                equivalent to the level of vehicle you could
                                receive in the US for the maximum lease value of
                                US $750/month for personal and business use (or
                                allowance for such vehicle). Type of vehicle
                                subject to approval by the CEO.

                                LEASE CANCELLATION: The Company will pay the
                                lease cancellation fees and any lost equity on
                                your two (2) personal vehicles.

BENEFITS:                       If you remain on or partially on, the US payroll
                                you will continue to be eligible to participate
                                in James Hardie Building Products, Inc's 401(K)
                                plan and all Company paid insurance plans. US
                                Social Security payments will continue to be
                                deducted from your pay and paid on your behalf.

                                If you are not eligible to participate in James
                                Hardie Building Products' 401(K) plan or social
                                security, the Company will pay to you directly
                                the annual IRS maximum contribution to the
                                401(K), instead of the dollar for dollar match
                                up to 6% of your pay up to the IRS maximum.

                                You will continue to be eligible for all other
                                GMT level benefits during your assignment,
                                including but not limited to Business Class
                                International Air travel and Executive Health
                                and Wellness.

CONTINUED COMPLIANCE WITH       During your assignment, you will be subject to
COMPANY POLICIES:               and expected to comply with all James Hardie
                                policies and agreements you have signed with the
                                Company, unless stated otherwise in this letter.
                                This includes any confidentiality,
                                noncompetition, and assignment of inventions
                                agreements that you have signed during your
                                employment with the Company.

PERSONAL ACCIDENT INSURANCE:    The Company provides 24-hour business travel
                                accident insurance for all international
                                assignees.

GROUP HEALTH INSURANCE:         As an expatriate employee, you have the same
                                Life, Medical, Dental, Vision and Disability
                                benefits as US based employees of JHBP. If you
                                require medical, dental or vision care during
                                your assignment, the Company expects that you
                                will make reasonable efforts to obtain that care
                                while you are in the US on home leave, business
                                trips, or vacation. However, in the event that
                                you are required to obtain medical, dental or
                                vision care in Amsterdam, your medical benefits
                                will be paid at the PPO level of benefits for
                                services rendered outside the US since the PPO
                                Group Health Insurance Plan has no specific
                                contracted providers in your region. Under such
                                circumstances, the Company will pay the
                                difference in fees/costs incurred by you under
                                its group health insurance plan for services
                                rendered by an out-of-network PPO provider.

RELOCATION CONDITIONS:

IMMIGRATION:                    The Company will process your residence and work
                                permits as applicable. Your employment in
                                Amsterdam will be contingent upon successfully
                                attaining the appropriate permits.

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                                                                    Exhibit 4.10

TRANSFER OF PERSONAL EFFECTS:   SHIPPING: The reasonable cost of packing,
                                freight and insurance in transit of your
                                household goods and personal effects (excluding
                                items of unique high value (e.g. pianos)) will
                                be paid by JHINV.

                                STORAGE: Items of value that are not shipped may
                                be placed in commercial storage at the
                                employee's home base. The Company will also
                                cover the reasonable cost for storage, removal
                                into storage and insurance on storage items of
                                items of value not shipped.

PET TRANSPORT:                  The Company will pay to transport your four (4)
                                dogs to Amsterdam at an estimated cost of US
                                $5000.

TEMPORARY LIVING EXPENSES:      Until your personal goods arrive in Amsterdam,
                                the Company will pay for furniture rental at the
                                new location for up to sixty (60) days.

ACCOMMODATION IN AMSTERDAM:     HOUSING ALLOWANCE: During your assignment in
                                Amsterdam the Company will provide you with a
                                net monthly housing allowance of 6,000 euros per
                                month. This allowance will be paid through the
                                Netherlands payroll. These funds are to cover
                                the cost of housing during your assignment and
                                your monthly housing utility costs (including
                                all traditional utilities, power, water, cable
                                and internet hook-up, and basic telephone
                                service). You will be responsible for all your
                                personal expenses - food, cleaning products,
                                groceries, clothing, etc.

                                VOLTAGE ALLOWANCE: The Company will provide a
                                one-time gross lump sum Voltage Allowance of
                                US$25,000. This allowance is to off-set the
                                additional expenses you will incur during this
                                relocation to Amsterdam.

                                LEASE CANCELLATION: The Company will pay the
                                lease cancellation fees on your current US
                                apartment, which includes a $3,000 per month
                                lease payment (for one month), plus any
                                associated expenses incurred in terminating the
                                lease early. Any loss of deposits as a result of
                                your pets, or cleaning will not be covered by
                                the Company.

LIABILITY FOR TAX PAYMENTS:     You will be tax equalized to the State of
                                Florida for the period of your international
                                assignment. Tax equalization is intended to
                                ensure that you pay no more than you would have
                                paid in taxes on covered income than had you not
                                been assigned overseas. The tax liability you
                                incur during your overseas assignment should be
                                the same as that of a domestic employee under
                                similar economic circumstances. You will be
                                reimbursed for any U.S. or foreign taxes that
                                you are required to pay beyond the U.S. and
                                Florida taxes you would have incurred on your
                                base salary, bonus (if any), imputed income from
                                group life insurance, and any other covered
                                income had you not accepted this overseas
                                assignment.

                                While you are on assignment, you will pay a
                                hypothetical tax in lieu of actual tax
                                liabilities. The hypothetical tax is intended to
                                be representative of your tax responsibilities
                                while on assignment. We will have Ernst & Young
                                calculate the amount to be withheld.

TERM AND TERMINATION:

TERM:                           As stated above, this assignment is expected to
                                last for a period of approximately three (3)
                                years. This period will not be extended beyond
                                approximately three (3) years except by the
                                mutual agreement of the parties. If an extension
                                is agreed to by the parties, you and the Company
                                will determine if the terms and conditions in
                                this contract will continue to apply or if the
                                Company will be converting you to a local
                                package.

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                                                                    Exhibit 4.10

                                During your assignment with JHINV, you shall
                                continue to remain an at-will employee. Thus,
                                notwithstanding the term of this assignment,
                                either you or the Company can terminate the
                                employment relationship at any time and for any
                                reason. However, in the event that you wish to
                                terminate this assignment, we request that you
                                provide your manager with one (1) months' notice
                                in writing. JHBP will extend you the same
                                courtesy with respect to this assignment,
                                although it reserves the right to pay you one
                                month's salary in lieu of notice. If your
                                assignment is terminated by JH for breach of
                                conditions applying to your employment, as
                                defined below, your employment with the Company
                                will terminate at the same time as your
                                assignment and you will not be entitled to
                                repatriation benefits, reinstatement or
                                severance.

                                For purposes of this letter, you will be in
                                breach of conditions applying to your employment
                                for engaging in unlawful harassment or
                                discrimination, substance abuse, theft, or
                                dishonesty; falsification of any Company
                                records; improper disclosure of the Company's
                                confidential or proprietary information; any
                                action by you which has a material detrimental
                                effect on the Company's reputation or business;
                                insubordination; your failure or inability to
                                perform any assigned duties (which are in
                                keeping with duties normally performed by a
                                General Counsel) after reasonable notice from
                                the Company of such failure or inability; or
                                your conviction (including any plea of guilty or
                                no contest) for any criminal act that impairs
                                your ability to perform your duties under this
                                agreement.

TERMINATION OF ASSIGNMENT:      In the event this assignment is terminated by
                                JHINV or you, JHINV will pay reasonable
                                repatriation costs for you and your belongings
                                to the United States as described below, unless
                                you were in breach of conditions applying to
                                your employment.

                                If you are terminated by the Company prior to
                                the completion of this assignment for breach of
                                conditions applying to your employment, or you
                                voluntarily terminate your assignment before the
                                end of its term, you agree to pay back all
                                relocation costs (pro-rated), which the Company
                                has paid to you or for you associated with your
                                relocation from the US to Amsterdam.

30% TAX RULING:                 1) If and to the extent that you will be
                                eligible for a tax-free reimbursement for
                                extra-territorial expenses based on Article 9 of
                                the 1965 Dutch Wage Tax Implementation Decree
                                ('Uitvoeringsbesluit loonbelasting 1965'), it
                                will be agreed that the remuneration for present
                                employment ('loon uit tegenwoordige
                                dienstbetrekking') as agreed with you will be
                                reduced for labor law purposes in such a way
                                that 100/70 of the thus agreed remuneration for
                                present employment is equal to the originally
                                agreed remuneration for present employment.

                                2) If and to the extent that part 1 is applied,
                                you shall receive from the company a
                                reimbursement for extra-territorial expenses
                                equal to 30/70 of the thus agreed remuneration
                                for present employment.

                                3) You are aware of the fact that adjustment of
                                the agreed remuneration pursuant to part 1 may
                                in view of the applicable regulations have
                                consequences for all remuneration - related
                                benefits and payments.

                                4) The "agreed remuneration for present
                                employment " as described in part 1 concerns all
                                the actual to-be-paid or to-be-provided
                                remuneration for present employment as described
                                in the 1964 Dutch Wage Tax Act and the
                                provisions based on it.

                                If the Dutch tax authorities publish additional
                                guidelines regarding the 30% - facility, this
                                agreement will be adjusted accordingly, if
                                necessary.

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                                                                    Exhibit 4.10

REPATRIATION/REINSTATEMENT CONDITIONS:

REPATRIATION TO THE U.S.:       If eligible for repatriation as described above,
                                JHINV will pay reasonable repatriation costs for
                                you to return to the United States, including
                                return business class airfare between Amsterdam
                                and California. JHINV will also pay reasonable
                                costs associated with the shipment of your
                                belongings from Amsterdam to California. In
                                addition, you will be provided with tax
                                assistance in relation to your return to the
                                U.S.

                                Repatriation must occur within six (6) months of
                                the termination of this international assignment
                                for this clause to apply. The Company will not
                                pay for any repatriation costs incurred by you
                                beyond this six (6) month time frame.

This letter constitutes the entire agreement between you and the Company
regarding the terms and conditions of your international assignment, and
supersedes all prior negotiations, representations, or agreements between you
and the Company regarding the same. This agreement is to be construed in
accordance with the laws of the State of California. Any disputes arising out of
this agreement shall be heard and determined in the State of California.

In acknowledging your agreement to the terms and conditions of this assignment,
please sign and return to me the duplicate copy of this letter.

Yours sincerely,

/s/ Louis Gries
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LOUIS GRIES
CHIEF EXECUTIVE OFFICER

I have read and understood this letter and hereby accept the international
assignment to Amsterdam on the terms and conditions set forth herein.

Signed: /s/ Benjamin Butterfield
        ----------------------------------
        Benjamin Butterfield

Date: May 27, 2005

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