[Question]large_icon or relative path

[wikii]

Is there a way to get the large_icon or small_icon of an instance of UI::Command?

 cmd = UI;;Command.new("Tester") { UI.messagebox("Hello World") }    
 cmd.small_icon = "ToolPencilSmall.png"
 cmd.large_icon = "ToolPencilLarge.png"

command.large_icon does't work!

I have try to modify the instance_method "large_icon=" of UI::Command in a rb file like "c:/Command_.rb".

module UI
   class Command   
      attr_reader ;large_icon 
      alias_method ;old_large_icon=,;large_icon=
      def large_icon= (fn)
         @large_icon=fn
         old_large_icon=(fn)
      end
   end
end

It works .
But tool button will be shown without icon if program uses relative path to the icon file.
Like sandboxmenus.rb in "C:/Program Files/Google/Google SketchUp 7/Tools/Sandbox".

 #a segment of sandboxmenus.rb
 cmd = UI;;Command.new($tStrings.GetString("From Scratch")) { Sketchup;;active_model.select_tool FromScratchTool.new }
    cmd.small_icon = "Images/tbFlatTerrainSmall.png"
    cmd.large_icon = "Images/tbFlatTerrainLarge.png"

It seems that "Images/tbFlatTerrainSmall.png" is treated as "c:/Images/tbFlatTerrainSmall.png" instead of "C:/Program Files/Google/Google SketchUp 7/Tools/Sandbox/Images/tbFlatTerrainSmall.png".