For an Access report, use the report Group and Sort option to define your sort order. That option over-rides any sort order established by the ORDER BY
clause in the report's record source query.
I don't recall exactly where that option is found in the Access 2003 user interface, but suspect you can track it down. Meanwhile be aware that Microsoft will discontinue support for Office 2003 in April 2014.
Here is a screenshot from Access 2007 which shows where the option is located on the ribbon interface.