FULL PRODUCT VERSION :
java version "1.6.0_01"
Java(TM) SE Runtime Environment (build 1.6.0_01-b06)
Java HotSpot(TM) Client VM (build 1.6.0_01-b06, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows [Version 6.0.6000]

A DESCRIPTION OF THE PROBLEM :
On Windows Vista, the tree control highlight is light blue with a slightly lighter blue outline (this is using the default colour theme, needless to say it's configurable but all the default themes use a light colour.)

On Swing JTrees, the highlight colour is a solid, darker blue, with no outline at all.

The Windows LAF is probably looking up the general (text) highlight colour and using it to highlight the tree items. This is similar to what used to happen with menu items in Java 6 before Update 1.



REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;
import javax.swing.*;
public class WrongTreeHighlight extends JFrame {
  public WrongTreeHighlight() {
    setLayout(new BorderLayout());
    add(new JTree(), BorderLayout.CENTER);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setSize(200, 200);
  }
  public static void main(String[] args) throws Exception {
    UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
    new WrongTreeHighlight().setVisible(true);
  }
}
---------- END SOURCE ----------