Synthetica Look And Feel, como configurar?

Olá, estou com o pacote do synthetica aqui, mas quando executo ele me traz o seguinte erro. E sim, ja estou compilando com o JDK6, segue abaixo o erro se puderem me ajudar eu fico muito agradecido xD

Exception in thread "AWT-EventQueue-0" java.lang.NoClassDefFoundError: sun/swing/plaf/synth/SynthUI at de.javasoft.plaf.synthetica.SyntheticaDefaultLookup.getDefault(SyntheticaDefaultLookup.java:84) at sun.swing.DefaultLookup.get(DefaultLookup.java:125) at javax.swing.plaf.basic.BasicButtonListener.getInputMap(BasicButtonListener.java:119) at javax.swing.plaf.basic.BasicButtonListener.installKeyboardActions(BasicButtonListener.java:95) at javax.swing.plaf.basic.BasicButtonUI.installKeyboardActions(BasicButtonUI.java:138) at javax.swing.plaf.basic.BasicButtonUI.installUI(BasicButtonUI.java:90) at javax.swing.JComponent.setUI(JComponent.java:664) at javax.swing.AbstractButton.setUI(AbstractButton.java:1807) at javax.swing.JButton.updateUI(JButton.java:146) at javax.swing.AbstractButton.init(AbstractButton.java:2172) at javax.swing.JButton.<init>(JButton.java:136) at javax.swing.JButton.<init>(JButton.java:90) at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel.installCompatibilityDefaults(SyntheticaLookAndFeel.java:553) at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel.access$4(SyntheticaLookAndFeel.java:405) at de.javasoft.plaf.synthetica.SyntheticaLookAndFeel$2.propertyChange(SyntheticaLookAndFeel.java:313) at java.beans.PropertyChangeSupport.fire(PropertyChangeSupport.java:335) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:327) at javax.swing.event.SwingPropertyChangeSupport.firePropertyChange(SwingPropertyChangeSupport.java:92) at java.beans.PropertyChangeSupport.firePropertyChange(PropertyChangeSupport.java:263) at javax.swing.UIManager.setLookAndFeel(UIManager.java:545) at TESTE.<init>(TESTE.java:13) at TESTE$1.run(TESTE.java:70) at java.awt.event.InvocationEvent.dispatch(InvocationEvent.java:251) at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:727) at java.awt.EventQueue.access$200(EventQueue.java:103) at java.awt.EventQueue$3.run(EventQueue.java:688) at java.awt.EventQueue$3.run(EventQueue.java:686) at java.security.AccessController.doPrivileged(Native Method) at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:76) at java.awt.EventQueue.dispatchEvent(EventQueue.java:697) at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:242) at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:161) at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:150) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:146) at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:138) at java.awt.EventDispatchThread.run(EventDispatchThread.java:91) Caused by: java.lang.ClassNotFoundException: sun.swing.plaf.synth.SynthUI at java.net.URLClassLoader$1.run(URLClassLoader.java:366) at java.net.URLClassLoader$1.run(URLClassLoader.java:355) at java.security.AccessController.doPrivileged(Native Method) at java.net.URLClassLoader.findClass(URLClassLoader.java:354) at java.lang.ClassLoader.loadClass(ClassLoader.java:423) at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at java.lang.ClassLoader.loadClass(ClassLoader.java:356) ... 36 more

Estou com o mesmo problema, conseguiu resolver;