On JDK 1.4.X (and also JDK 1.5) some very large glyphs that are algorithmically
bolded display incorrectly - the paths that are generated by T2K are apparently
incorrect. The same happens whether the JDK obtains a bitmap from T2K and
blits that, or obtains a shape and fills that, so the problem appears to be
in T2K.
It has been claimed this problem starts to show up with pt sizes > 400

here's a test case that shows the problem on Solaris 9 at 600 pt but not 599pt
import java.awt.*;

public class BigCJK extends Component {

   private Image image;
   private Graphics graphics;

   public Dimension getPreferredSize() {
      return(new Dimension(1200,800));
   }

   public void paint(Graphics theGraphics) {

      if (image == null) {
         image = createImage(getSize().width, getSize().width);
      }
      graphics = image.getGraphics();
      graphics.setColor(Color.white);
      graphics.fillRect(0,0,getSize().width, getSize().width);
      //Font f = new Font("FZFangSongTi", Font.BOLD, 599);
      Font f = new Font("FZFangSongTi", Font.BOLD, 600);
      graphics.setFont(f);
      graphics.setColor(Color.black);
      graphics.drawString("\u3401", 500, 500);
      theGraphics.drawImage(image,0,0,this);
   }

   public static void main(String [] args) {
      Frame f = new Frame();
      BigCJK cjk = new BigCJK();
      f.add(cjk,BorderLayout.CENTER);
      f.pack();
      f.setVisible(true);
   }