Get Workflow protocol

Hello.

for our workflow regarding Purchase Order release strategy we need to know which

agent has processed the last release (=Workitem).

Now i found FM "SAP_WAPI_DIALOG_PROTOCOL". This FM shows up the needed

information in tab "Workflow objects" in dialog.

But anybody knows how to get this information from the database tables ? Or is there

any FM or class which will provide this information without dialog ?

Thanks a lot.

Sebastian