Invoice Verification: Workflow links not displayed

[Becker Stephan (extern)]

Hi everybody,
 
I am trying to display links of an invoice to workflows in FB03 using the
button object services, and then the menu workflow.. workflow overview). The
system (4.6C) looks in table SWIWIOBJCT for anything with a BKPF object
type. However, invoice verification uses BSEG_MMIV and BUS2081 and thus no
workflow links are displayed. Is this an SAP "feature" or am I missing
something?
 
Thanks,
Stephan Becker