##### 



Exhibit 12.1
 CERTIFICATION OF CHIEF EXECUTIVE OFFICER
PURSUANT TO SECTION 302 OF THE SARBANES-OXLEY ACT OF 2002
  1.
    
    I have reviewed this amendment to annual report on Form 20-F/A No. 1 of James Hardie Industries N.V.;2.
    
    Based on my knowledge, this report does not contain any untrue statement of a material fact or omit to state a
material fact necessary to make the statements made, in light of the circumstances under which such statements
were made, not misleading with respect to the period covered by this report;3.
    
    Based on my knowledge, the financial statements, and other financial information included in this report, fairly
present in all material respects the financial condition, results of operations and cash flows of the company as
of, and for, the periods presented in this report;4.
    
    The companys other certifying officer and I are responsible for establishing and maintaining disclosure controls
and procedures (as defined in Exchange Act Rules 13a-15(e) and 15d-15(e)) and internal control over financial
reporting (as defined in Exchange Act Rules 13a-15(f) and 15d-15(f))for the company and have:
 a)
    
    Designed such disclosure controls and procedures, or caused such
disclosure controls and procedures to be designed under our supervision,
to ensure that material information relating to the company, including
its consolidated subsidiaries, is made known to us by others within those
entities, particularly during the period in which this report is being
prepared;b)
    
    Designed such internal control over financial reporting, or caused such
internal control over financial reporting to be designed under our
supervision, to provide reasonable assurance regarding the reliability of
financial reporting and the preparation of financial statements for
external purposes in accordance with generally accepted accounting
principles;c)
    
    Evaluated the effectiveness of the companys disclosure controls and
procedures and presented in this report our conclusions about the
effectiveness of the disclosure controls and procedures, as of the end of
the period covered by this report based on such evaluation; andd)
    
    Disclosed in this report any change in the companys internal control
over financial reporting that occurred during the period covered by the
annual report that has materially affected, or is reasonably likely to
materially affect, the companys internal control over financial
reporting; and
 5.
    
    The companys other certifying officer and I have disclosed, based on our most recent evaluation of internal
control over financial reporting, to the companys auditors and the audit committee of the companys board of
directors (or persons performing the equivalent functions):
 a)
    
    All significant deficiencies and material weaknesses in the design or
operation of internal control over financial reporting which are
reasonably likely to adversely affect the companys ability to record,
process, summarize and report financial information; andb)
    
    Any fraud, whether or not material, that involves management or other
employees who have a significant role in the companys internal control
over financial reporting.
 Date: August 7, 2007
    /s/ Louis GriesLouis GriesChief Executive Officer