Compatibility problems between Excel 2003 SP3 and earlier versions

Hi,

Has anyone experienced compatibility issues between Excel 2003 SP3 and earlier versions?

I publish a workbook with a protected code module to users in a number of companies around the world with a variety of different excel versions. The sheet was created in 2003 SP2 and tested using excel 2000.

If a 2003 SP3 user saves the workbook, it either can not be opened by earlier versions, in some instances crashing excel, or a compile error shows when the earlier version users attempt to run macros. There are no 'true' compile errors in the code.

Does anyone else have experience of this problem and is there anything that can be done by SP3 users when saving the file to stop the compatibility issues?

Nick