changing scrollbar appearance

Mission might be impossible (but it is not as I see from applications running on the phone) but ...

How to properly change the appearance of scrollbars for the application. You know, if you create a standard app, the scrollbar "arrows" are placed in between of the softkey labels usually. I think it depends on the theme but usually the arrows are there. Now ... I want to change it for my application (and for my application only - not affecting the phone's theme) and to display a scrollbar as a actual (in the form we are used to see them) scrollbar on the right side of the scrollable content (menu, listbox).
How to achieve that?

rgds,
  Ahti.