[AccessD] OT: Excel Worksheet_Change event

Hi group
Say I have an Excel worksheet linked to an Access table or to another Excel workbook. When data in the Access table or the other Excel workbook changes and then updates my worksheet I want code to automatically perform some action. How to?
A first guess would be to use the Worksheet_Change event for the worksheet.
But problem is that this event only triggers when new data are manually *entered* in a cell, not when the cell *updates* being linked to an external source by reference, i.e. by a formula or a table link.
So calling any Excel genius on this list...
Asger