AutoFilter

If an entire row or column within the data is blank then that row or column will be the limit of the filter

is that a 2003 thing ? its certainly not true in 97 or 2007 or are we at cross purposes here?

It should depend on what you select to start with. If you select one cell, then you'll get the current region (which will stop at a blank row); if you select all the data first, you'll be fine.