The fix for BugID 4362381 introduced a new, non-public, inner class to
CardLayout.java: Card. Although CardLayout is Serializable, Card was not
declared Serializable. The prevents client code from Serializing CardLayout.

You can easily reproduce this bug using the existing regression test
test/java/awt/CONFORMANCE.

/net/jano/export/disk03/awt/dpm/merlin/test/java/awt/CONFORMANCE -> /usr/local/java/jdk1.4/solsparc/bin/java AWTConformanceTest
java.io.NotSerializableException: java.awt.CardLayout$Card
        at java.io.ObjectOutputStream.outputObject(ObjectOutputStream.java:1148)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:366)
        at java.io.ObjectOutputStream.outputArray(ObjectOutputStream.java:1098)
        at java.io.ObjectOutputStream.checkSubstitutableSpecialClasses(ObjectOutputStream.java:456)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:361)
        at java.io.ObjectOutputStream.outputClassFields(ObjectOutputStream.java:1841)
        at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:480)
        at java.io.ObjectOutputStream.outputObject(ObjectOutputStream.java:1214)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:366)
        at java.io.ObjectOutputStream.outputClassFields(ObjectOutputStream.java:
1841)
        at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:480)
        at java.io.ObjectOutputStream.outputObject(ObjectOutputStream.java:1214)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:366)
        at java.io.ObjectOutputStream.outputClassFields(ObjectOutputStream.java:1841)
        at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:480)
        at java.awt.Container.writeObject(Container.java:2429)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.io.ObjectOutputStream.invokeObjectWriter(ObjectOutputStream.java:1878)
        at java.io.ObjectOutputStream.outputObject(ObjectOutputStream.java:1210)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:366)
        at java.io.ObjectOutputStream.outputArray(ObjectOutputStream.java:1098)
        at java.io.ObjectOutputStream.checkSubstitutableSpecialClasses(ObjectOutputStream.java:456)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:361)
        at java.io.ObjectOutputStream.outputClassFields(ObjectOutputStream.java:1841)
        at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:480)
        at java.awt.Container.writeObject(Container.java:2429)
        at java.lang.reflect.Method.invoke(Native Method)
        at java.io.ObjectOutputStream.invokeObjectWriter(ObjectOutputStream.java:1878)
        at java.io.ObjectOutputStream.outputObject(ObjectOutputStream.java:1210)
        at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:366)
        at AWTConformanceTest.saveSerializedFile(AWTConformanceTest.java:431)
        at AWTConformanceTest.saveSerialize(AWTConformanceTest.java:463)
        at AWTConformanceTest.actionPerformed(AWTConformanceTest.java:373)
        at AWTConformanceTest.actionPerformed(AWTConformanceTest.java:337)
        at java.awt.MenuItem.processActionEvent(MenuItem.java:540)
        at java.awt.MenuItem.processEvent(MenuItem.java:504)
        at java.awt.MenuComponent.dispatchEventImpl(MenuComponent.java:276)
        at java.awt.MenuComponent.dispatchEvent(MenuComponent.java:266)
        at java.awt.MenuComponent.dispatchEventImpl(MenuComponent.java:278)
        at java.awt.MenuComponent.dispatchEvent(MenuComponent.java:266)
        at java.awt.EventQueue.dispatchEvent(EventQueue.java:425)
        at java.awt.EventDispatchThread.pumpOneEvent(EventDispatchThread.java:136)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:122)
        at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:118)
        at java.awt.EventDispatchThread.run(EventDispatchThread.java:98)
Serialization error -- please file a bug report