FULL PRODUCT VERSION :
java version "1.6.0-rc"
Java(TM) SE Runtime Environment (build 1.6.0-rc-b103)
Java HotSpot(TM) Client VM (build 1.6.0-rc-b103, mixed mode)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows 2000 [Version 5.00.2195]

A DESCRIPTION OF THE PROBLEM :
MouseEvent.isAltDown() returns true when middle mouse button is pressed

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
Attach MouseListener, print result of isAltDown() when mouse button pressed. Press middle mouse button WITHOUT holding the Alt-key down. true is returned.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Method should reflect the state of the Alt-key.
ACTUAL -
Returns always true when middle button is pressed.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;


public class Test
{
	public static void main(String ... args)
	{
		try
		{
			JFrame frame = new JFrame();
			frame.getContentPane().addMouseListener(new MouseAdapter()
			{
				public void mousePressed(MouseEvent e)
				{
					System.out.print(e.isAltDown());
				}
			});
			frame.setSize(800,600);
			frame.setVisible(true);
		}
		catch(Exception e)
		{
			e.printStackTrace();
		}
	}
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
Unknown.