There are a number of issues with scrollbars under the GTK L&F such that they do
not match native ones, especially under the clearlooks and ubuntulooks engines
and the Human theme used on Ubuntu 6.06:
  1) scrollbar buttons are not rounded as they should be on ubuntulooks/clearlooks
  2) scrollbar thumb should respect native minimum size property
  3) scrollbar not positioned correctly when used in a scrollpane
       a) scrollbar should be flush with viewport edges
       b) scrollbar should be a certain distance away from viewport edge