Hi Thomas,
thank you for the hint. The 'duplicate' menu item is only in the context menu of the project explorer.
I was looking for it in the edit menu and the context menu of the outline of the object to be copied... but the copy menu item just copies the name of the object, not the object itselve. I think I was misleaded by SE80 where the duplication is called 'copy'.
So thank you one more time,
Peter