About Graphics.setClip()

when I use g.setClip(x, y, w, h) in the componet AbstractWidget's paintContent method to limited child component's area, a strange thing occured: child component's style(border, background, padding, margin) just display a part, but child component could display completely, the codes similiar like below:

                g.setClip(getX(), getY(), w, h);  //limit display area
		renderStyle(g); //paint child component's style
                paintImpl(g);   //paint child component

but at fellow's computer it could display right, very strange, after my test I modified codes like below:

               g.setClip(getX(), getY(), w + getX(), h + getY());
               ...

it runs right! but at fellow's computer it runs not right. I'm puzzled, maybe it's the version of WTK's fault, then I install the latest WTK2.5.2, the problem solved. So

               g.setClip(getX(), getY(), w + getX(), h + getY()); //fixed for WTK2.5.1
               ...

maybe the fault of WTK2.5.1