The problem was found when one of our licensees migrating their
customer's application from jdk 1.3.1 to jdk 5.0.

It is easy to reproduce it with the following test program. I reproduced
it against jdk 1.3.1_21, jdk 5.0u13 and jdk 6.0u2 on Windows XP.

----->
import java.awt.Frame;
import java.awt.SystemColor;
import java.awt.TextField;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
public class TP extends Frame {
public TP() {
this.setBounds(300, 300, 300, 300);
this.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent arg0) {
super.windowClosing(arg0);
System.exit(0);
}
});
TextField fs = new TextField();
fs.setBackground(SystemColor.text);

this.add(fs);
}
public static void main(String[] args) {
new TP().setVisible(true);
}
}
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I also attached a screenshot that explains the problem.