FULL PRODUCT VERSION :
java version "1.6.0_10-rc"
Java(TM) SE Runtime Environment (build 1.6.0_10-rc-b28)
Java HotSpot(TM) Client VM (build 11.0-b15, mixed mode, sharing)

javac 1.6.0_10-rc

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

EXTRA RELEVANT SYSTEM CONFIGURATION :
Graphics Card: NVIDIA Quadro NVS 280 SD
resolution set at: 1280 x 1024 pixels
32-bit color

A DESCRIPTION OF THE PROBLEM :
Using Nimbus Look and Feel, the text displayed in a JTextField is cut off at the bottom. The same program displays correctly using the default Metal L&F and Windows L&F. The JTextField's GridBag constraints are:

        tfUserName = new JTextField();
        tfUserName.setPreferredSize(new Dimension(100, 25));
        tfUserName.setMinimumSize(new Dimension(80, 25));
        tfUserName.setAlignmentY(JTextField.TOP_ALIGNMENT);
        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.weighty = 1.0;
        gridBagConstraints.gridwidth = 1;
        gridBagConstraints.gridheight = 1;
        gridBagConstraints.insets = new Insets(4,4,-4,4);
        gridBagConstraints.insets.bottom = 4;
        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 3;
        gridBagConstraints.anchor = GridBagConstraints.SOUTHWEST;
        gridBagLayout.setConstraints(tfUserName, gridBagConstraints);


STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
The source code entered below includes two classes, MvMain and LoginPanel. In MvMain.initApp() is a call to UIManager.setLookAndFeel(). This sets the Look and Feel to Nimbus L&F. You can change which L&F is set in order to compare the painting of the JTextField with the default or other L&F's. MvMain displays the name of the look and feel in use in the window title.

When the program is running, type the string: "joypaqg" (i.e. any letters that have descending parts) in the Username JTextField. You will see that the lower parts of letters with descending parts are missing.

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
I expected to see all of the letters that I type, including their descending parts.
ACTUAL -
All lower-case letters with descending parts are missing their descending parts.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
No error messages are produced. The displayed text is just incorrectly painted.

REPRODUCIBILITY :
This bug can be reproduced always.

---------- BEGIN SOURCE ----------
import java.applet.Applet;
import java.applet.AppletContext;
import java.awt.Color;
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.Frame;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.net.MalformedURLException;
import java.net.URL;
import java.util.Enumeration;
import java.util.StringTokenizer;

import java.awt.BorderLayout;
import javax.swing.JOptionPane;
import javax.swing.JFrame;
import javax.swing.JPopupMenu;
import javax.swing.ProgressMonitor;
import javax.swing.SwingUtilities;
import javax.swing.UIManager;

public class MvMain extends JFrame
{
    private static final long serialVersionUID = -6271057902984678813L;
    
    protected Dimension SCREEN_SIZE = null;
    private JFrame loginFrame;


    private String presetUserName = null;
    private String presetPassword = null;
    
    // main
    public static void main(String args[])
    {
        
        new MvMain();
    }

    // Mv
    public MvMain()
    {
        this(null);
    }

    public MvMain(String withUserName, String withPassword)
    {
        super("Nimbus JTextField Test");

       presetUserName = withUserName;
       presetPassword = withPassword;

       initApp(null);
    }

    // Mv
    public MvMain(AppletContext withAppletContext)
    {
        super("Nimbus JTextField Test");
        initApp(withAppletContext);
    }

    private void initApp(AppletContext withAppletContext)
    {
        /**
         * ensures that menu's rise above any heavy weight elements
         * This is critical for WebRenderer.
         */
        JPopupMenu.setDefaultLightWeightPopupEnabled(false);

        try {
        
            UIManager.setLookAndFeel(
                "com.sun.java.swing.plaf.nimbus.NimbusLookAndFeel");
 // "com.sun.java.swing.plaf.windows.WindowsLookAndFeel");

        } catch (Exception e) { }


        Color base = new Color(236,233,216);


        // launch login
        launchLoginFrame();

    }


    // getLoginFrame
    public JFrame getLoginFrame()
    {
        return loginFrame;
    }

    // launchLoginFrame
    private void launchLoginFrame()
    {
        setLoginFrame(new JFrame("L&F: " + UIManager.getLookAndFeel().getName()));
        getLoginFrame().setSize(300,250);
        getLoginFrame().getContentPane().add(new LoginPanel( getLoginFrame(),null),BorderLayout.CENTER);

        if ((presetUserName != null) && (presetPassword != null))
        {
          // test harness -- bypass the login dialog box!!!!
          return;
        }

        getLoginFrame().setVisible(true);

    }



    // setLoginFrame
    protected void setLoginFrame(JFrame value)
    {
        loginFrame = value;
    }


}

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Frame;
import java.awt.GridBagConstraints;
import java.awt.GridBagLayout;
import java.awt.Insets;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JPasswordField;
import javax.swing.JTextField;
import javax.swing.SwingConstants;

public class LoginPanel extends JPanel {

private static final long serialVersionUID = 1612748376439346956L;
public LoginPanel(
        JFrame withLoginFrame,
        String withUserName)
    {
super();
        
        setVisible(true);
        
        setLoginFrame(withLoginFrame);
        setLayout(new BorderLayout(0,2));

        // components
        GridBagLayout gridBagLayout;
        GridBagConstraints gridBagConstraints;

        gridBagLayout = new GridBagLayout();
        gridBagConstraints = new GridBagConstraints();
        JPanel body_wrapper = new JPanel(gridBagLayout);
        
        JLabel lblBannerImage = new JLabel("LOGO_BANNER");
        JLabel lblVersion = new JLabel("Version: " + "5.5");
        JLabel lblUserName = new JLabel("User Name:");
        JLabel lblPassword = new JLabel("Password:");
        
        JLabel tunnelHrefLabel = new JLabel("Proxy");
        tunnelHrefLabel.setForeground(Color.BLUE);
        tunnelHrefLabel.addMouseListener(new LoginMouseListener(this));
        
        tfUserName = new JTextField();
        tfUserName.setPreferredSize(new Dimension(100, 25));
        tfUserName.setMinimumSize(new Dimension(80, 25));
        tfUserName.setAlignmentY(JTextField.TOP_ALIGNMENT);
        lblUserName.setLabelFor(tfUserName);
        tfUserName.setVisible(true);
        tfPassword = new JPasswordField();
        tfPassword.setPreferredSize(new Dimension(100, 25));
        tfPassword.setMinimumSize(new Dimension(80, 25));
        tfPassword.setAlignmentY(JTextField.TOP_ALIGNMENT);
        lblPassword.setLabelFor(tfPassword);
        tfPassword.setVisible(true);
        
        btnCancel = new JButton("BTN_CANCEL");
        btnCancel.setPreferredSize(new Dimension(40,25));

        btnLogin = new JButton("BTN_LOGIN");
        btnLogin.setPreferredSize(new Dimension(40,25));


        // layout

        gridBagConstraints.weightx = 1.0;
        gridBagConstraints.weighty = 1.0;
        gridBagConstraints.gridwidth = 1;
        gridBagConstraints.gridheight = 1;
        gridBagConstraints.insets = new Insets(4,4,-4,4);

        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 0;
        gridBagConstraints.gridwidth = 2;
        gridBagConstraints.anchor = GridBagConstraints.SOUTH;
        gridBagLayout.setConstraints(lblBannerImage, gridBagConstraints);
        body_wrapper.add(lblBannerImage);

        gridBagConstraints.insets.bottom = 8;

        lblVersion.setForeground(Color.darkGray);
        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 1;
        gridBagConstraints.gridwidth = 2;
        gridBagConstraints.anchor = GridBagConstraints.CENTER;
        gridBagLayout.setConstraints(lblVersion, gridBagConstraints);
        body_wrapper.add(lblVersion);

        gridBagConstraints.insets.bottom = 4;

        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 3;
        gridBagConstraints.gridwidth = 1;
        gridBagConstraints.anchor = GridBagConstraints.SOUTHEAST;
        gridBagLayout.setConstraints(lblUserName, gridBagConstraints);
        body_wrapper.add(lblUserName);

        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 3;
        gridBagConstraints.anchor = GridBagConstraints.SOUTHWEST;
        gridBagLayout.setConstraints(tfUserName, gridBagConstraints);
        body_wrapper.add(tfUserName);

        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 4;
        gridBagConstraints.anchor = GridBagConstraints.NORTHEAST;
        gridBagLayout.setConstraints(lblPassword, gridBagConstraints);
        body_wrapper.add(lblPassword);

        gridBagConstraints.gridx = 1;
        gridBagConstraints.gridy = 4;
        gridBagConstraints.anchor = GridBagConstraints.NORTHWEST;
        gridBagLayout.setConstraints(tfPassword, gridBagConstraints);
        body_wrapper.add(tfPassword);

        JPanel bottom_wrapper = new JPanel(new FlowLayout(FlowLayout.RIGHT, 4, 1));
        bottom_wrapper.add(btnLogin);
        bottom_wrapper.add(btnCancel);
        JPanel buttonBottom = new JPanel(new BorderLayout());
        buttonBottom.add(bottom_wrapper, BorderLayout.CENTER);

        gridBagConstraints.gridx = 0;
        gridBagConstraints.gridy = 5;
        gridBagConstraints.gridwidth = 2;
        gridBagConstraints.anchor = GridBagConstraints.NORTHEAST;
        gridBagLayout.setConstraints(buttonBottom, gridBagConstraints);
        body_wrapper.add(buttonBottom);

        if (withUserName != null) {
          tfUserName.setText(withUserName);
          tfUserName.setEnabled(false);
        }
        
        add(body_wrapper, BorderLayout.CENTER);
    
        JPanel hyperPanel = new JPanel(new BorderLayout());
        hyperPanel.add(tunnelHrefLabel, BorderLayout.EAST);
        add(hyperPanel, BorderLayout.SOUTH);
    }


    /**
     * Sets the focus and default button when the panel is initially displayed.
     */
    public void setInitialFocus(){
        tfUserName.requestFocus();
        loginFrame.getRootPane().setDefaultButton(btnLogin);
    }

    // setButtonsEnabled
    public void setButtonsEnabled(boolean value){
        btnLogin.setEnabled(value);
        btnCancel.setEnabled(value);
    }


    // getLoginFrame
    public JFrame getLoginFrame(){
        return loginFrame;
    }

    // getLoginPanel
    public JPanel getLoginPanel(){
        return LoginPanel.this;
    }

    // getUserNameField
    public JTextField getUserNameField(){
        return tfUserName;
    }

    // getPasswordField
    public JPasswordField getPasswordField(){
        return tfPassword;
    }


    class LoginMouseListener implements MouseListener
    {
        private JPanel parent;
        public LoginMouseListener(JPanel parent)
        {
            super();
            this.parent=parent;
        }
        
        public void mouseClicked(MouseEvent e)
        {
            Component c = (Component) parent;
            while (!(c instanceof Frame))
            {
                c = c.getParent();
            }
        }
        
        public void mouseExited(MouseEvent e)
        {}
        
        public void mouseReleased(MouseEvent e)
        {}
        public void mousePressed(MouseEvent e)
        {}
        public void mouseEntered(MouseEvent e)
        {}
    }

    // setLoginFrame
    protected void setLoginFrame(JFrame value){
        loginFrame = value;
    }

    private JTextField tfUserName;
    private JPasswordField tfPassword;
    private JFrame loginFrame;
    private JButton btnLogin;
    private JButton btnCancel;

    
}
---------- END SOURCE ----------

CUSTOMER SUBMITTED WORKAROUND :
We have no workaround that allows the GUI to look good.

We are also having problems with the painting of JTextPane text in a Document used inside a JTable cell. In this case, more of the text disappears at the bottom, not just the letters' descending parts. These two problems are preventing us from using Nimbus L&F for our application. We will have to find some other, 3rd party L&F for the new release of our product.