MELBOURNE -- Standard&Poor's CreditWire 3/3/98 -- Standard&Poor's today raised its corporate credit rating on Leighton Holdings Ltd. (Leighton) to triple-'B'-plus from triple-'B', and revised the rating outlook to stable from positive. The rating on US$82 million senior unsecured notes also has been raised to triple-'B'-plus from triple-'B'. Leighton's rating change reflects Standard&Poor's expectation that the company will consolidate its demonstrated track record and established position as Australia's largest construction and contract mining group. In addition, Standard&Poor's expects that the company will continue to maintain sectoral, geographic, and project diversity across Australia and Asia, and a prudential profile appropriate for a company with cyclical contract risk exposures. Leighton management also is likely to