FULL PRODUCT VERSION :
java version "1.6.0-beta2"
Java(TM) SE Runtime Environment (build 1.6.0-beta2-b78)
Java HotSpot(TM) Client VM (build 1.6.0-beta2-b78, mixed mode, sharing)


ADDITIONAL OS VERSION INFORMATION :
SunOS voyager 5.11 snv_33 i86pc i386 i86pc

A DESCRIPTION OF THE PROBLEM :
JFileChooser component does not quite work as before w.r.t. double mouse click on a directory element - i.e., the directory element does not open as expected.

This used to work in the previous early snapshots of 1.6.0 - I think about four or five version behined the b78.

I think this issue is related to the interactions of the newer 1.6 builds with GNOME window manager, because, I could also replicate this problem on another platform (LINUX instead of Solaris x86) under GNOME.  However, when I switched the window manager to something other than GNOME, e.g., KDE then the double clicks worked without any problems.

EXPECTED VERSUS ACTUAL BEHAVIOR :
Please see attached file called unexpected_behaviour.png.? As shown, after double clicking the projects directory, instead of the GUI showing the contents of the directory,  the projects directory is selected such that you can rename the directory.? The expected_behaviour.png shows what I used to get in previous versions of 1.6.0, 1.5.x and below.

On executing the attached source code - Single clicking on a file, e.g., /home/saeed/signature.txt , and pressing the save button produces this:
f: /home/saeed/signature.txt
Single clicking on a directory, changes the save button to open button.
Double clicking on either a file or a directory causes the element to be highlighted so it can be either renamed or copied into clipboard.

REGRESSION.  Last worked in version mustang

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import javax.swing.*;
import java.io.*;
class test {
    public static void main(String[] args) {
	JFileChooser jfc = new JFileChooser();
	jfc.setFileSelectionMode(JFileChooser.FILES_ONLY);
	jfc.setDialogType(JFileChooser.SAVE_DIALOG);
	jfc.setMultiSelectionEnabled(false);
	int result = jfc.showSaveDialog(null);
	if (result == JFileChooser.APPROVE_OPTION)
	    {
          	File f = jfc.getSelectedFile();
		System.out.println("f: " + f);
                if (f == null) return;	
	    }
    }
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
A work around is to hold the Ctrl key at the same time as the mouse double click.

Release Regression From : mustang
The above release value was the last known release where this 
bug was known to work. Since then there has been a regression.