Track changes made to Invoice in VF02

Hi,

The scenario is as follows:

When an invoice is changed(any status change or tax information changes or any other field), i need to trigger some implementation of my own.

I could achieve this for Sales order through change document VERKBELEG and transaction SWEC. Change document FAKTBELEG doesnot work for the invoice in 'swec' in the same way. Is there anything missing? Or is there any way that i can track these changes and trigger some implementation?

Best Regards,

Varalaxmi