Java Derby with Squirrel SQL

I am using jre 1.6, java db 10.1.3.1, squirrel sql 2.4.1
I follow this instruction
http://db.apache.org/derby/integrate/SQuirreL_Derby.html#Configuring+SQuirreL+for+the+Derby+Embedded+JDBC+Driver
to set my driver (my driver is at C:\Sun\SDK\javadb\lib\derby.jar)

But I keep getting
org.apache.derby.iapi.services.context.ShutdownException:

followed is the stack trace:
org.apache.derby.iapi.services.context.ShutdownException:
      at org.apache.derby.iapi.services.context.ContextService.getFactory(Unknown Source)
      at org.apache.derby.jdbc.InternalDriver.<init>(Unknown Source)
      at org.apache.derby.jdbc.Driver20.<init>(Unknown Source)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
      at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
      at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
      at java.lang.reflect.Constructor.newInstance(Unknown Source)
      at java.lang.Class.newInstance0(Unknown Source)
      at java.lang.Class.newInstance(Unknown Source)
      at net.sourceforge.squirrel_sql.fw.sql.SQLDriverManager.registerSQLDriver(SQLDriverManager.java:75)
      at net.sourceforge.squirrel_sql.fw.sql.SQLDriverManager$MyDriverListener.propertyChange(SQLDriverManager.java:191)
      at java.beans.PropertyChangeSupport.firePropertyChange(Unknown Source)
      at java.beans.PropertyChangeSupport.firePropertyChange(Unknown Source)
      at net.sourceforge.squirrel_sql.fw.util.PropertyChangeReporter.firePropertyChange(PropertyChangeReporter.java:63)
      at net.sourceforge.squirrel_sql.fw.sql.SQLDriver.setJarFileNames(SQLDriver.java:281)
      at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.applyFromDialog(DriverInternalFrame.java:253)
      at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.performOk(DriverInternalFrame.java:230)
      at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame.access$200(DriverInternalFrame.java:60)
      at net.sourceforge.squirrel_sql.client.gui.db.DriverInternalFrame$3.actionPerformed(DriverInternalFrame.java:382)
      at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
      at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
      at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
      at javax.swing.DefaultButtonModel.setPressed(Unknown Source)
      at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
      at java.awt.Component.processMouseEvent(Unknown Source)
      at javax.swing.JComponent.processMouseEvent(Unknown Source)
      at java.awt.Component.processEvent(Unknown Source)
      at java.awt.Container.processEvent(Unknown Source)
      at java.awt.Component.dispatchEventImpl(Unknown Source)
      at java.awt.Container.dispatchEventImpl(Unknown Source)
      at java.awt.Component.dispatchEvent(Unknown Source)
      at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
      at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
      at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
      at java.awt.Container.dispatchEventImpl(Unknown Source)
      at java.awt.Window.dispatchEventImpl(Unknown Source)
      at java.awt.Component.dispatchEvent(Unknown Source)
      at java.awt.EventQueue.dispatchEvent(Unknown Source)
      at net.sourceforge.squirrel_sql.client.Application$1.dispatchEvent(Application.java:168)
      at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
      at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
      at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
      at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
      at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
      at java.awt.EventDispatchThread.run(Unknown Source)


What is the likely to be the problem? Any input  is welcome:)