Excel 2007 & 2003 VBA Compatibility

Hi,

I am using Excel 2007 and want to pass on some simple macros to someone who only has access to Excel 2003.

Given that the macro-enabled workbook format (xlsm) wasn't available in Excel 2003, can someone please tell me how to share the macros with a user of this version of the software? Is it best simply to send the code in a Word doc so that they can paste it into their VBE or can 2003 do anything with the xlsm file (e.g. with the addition of a compatibility package)?

Thanks