Toolbarbutton image doesn't dissapear..

i have a toolbarbutton is 'dirty' which uses a image on the button with setImage(image) 'pencil' when the data is store on the database i need to remove the image on the button. i use the following code.

public void cleanIconOnSelectedToolBarButton(java.util.ArrayList<Object>toolbarChildren)
{
CustomToolBarButton button =searchSelectedToolBarButton(toolbarChildren);
log.debug("searchSelectedToolbarButton: "+(button==null));//never null.........
if(button!=null)

{log.debug(button.getLabel()+"[before]"+button.getImage());button.setImage(null);log.debug("after:"+(button.getImage()==null));}

return;
}

console

2013-09-16 14:24:54,687 [http-bio-8080-exec-8] DEBUG com.ToolbarButtonUtilities - searchSelectedToolbarButton: false
2013-09-16 14:24:54,687 [http-bio-8080-exec-8] DEBUG com.ToolbarButtonUtilities - Materials[before]/img/background/pencil.png
2013-09-16 14:24:54,687 [http-bio-8080-exec-8] DEBUG com.ToolbarButtonUtilities - after:true

when i test the code i see the toolbarButton is 'dirty' and later i set the image to NULL later i test the button.getImage is NULL but i can still the pencil on the Toolbarbutton View...... i think is a bug... i hope you can help me out..