Comment 3 for bug 416030

That's really strange. Unfortunately I'm in summer break now and I don't have Ubuntu pc near me. Sorry I can't test. It worked with me before. But I have an idea if you are willing to edit some lines of the gtkrc file. The style to search for is :
'style "newwave-frame"'

it is empty in this release but I think it should not be. You should either not apply it by:

class "GtkFrame" style "newwave-frame"
widget_class "*.<GtkFrame>.*" style "newwave-frame"

or use null image for frame background like this:

style "newwave-frame"
{
  engine "pixmap"
  {
  image
 {

  function = SHADOW
                file = "Images/Others/null.png"
                border = {1, 1, 1, 1}
  stretch = TRUE
 }
  }
}

or try this out instead of the provided style for window:

style "newwave-window"
{
        bg_pixmap[NORMAL] = "Images/Others/null.png"
}