src/java.desktop/share/classes/javax/swing/plaf/metal/MetalRadioButtonUI.java

*** 242,252 ****
                     g.setColor(b.getForeground());
                 } else {
                     // *** paint the text disabled
                     g.setColor(getDisabledTextColor());
                 }
!                SwingUtilities2.drawStringUnderlineCharAt(c,g,text,
                         mnemIndex, textRect.x, textRect.y + fm.getAscent());
             }
             if(b.hasFocus() && b.isFocusPainted() &&
                textRect.width > 0 && textRect.height > 0 ) {
                 paintFocus(g,textRect,size);
--- 242,252 ----
                     g.setColor(b.getForeground());
                 } else {
                     // *** paint the text disabled
                     g.setColor(getDisabledTextColor());
                 }
!                getTextUIDrawing().drawStringUnderlineCharAt(c,g,text,
                         mnemIndex, textRect.x, textRect.y + fm.getAscent());
             }
             if(b.hasFocus() && b.isFocusPainted() &&
                textRect.width > 0 && textRect.height > 0 ) {
                 paintFocus(g,textRect,size);