JSeparator is not serializable in GTK while it can be serialized in other L&F's
Steps to reproduce:
1) Run the attached test TestSerializeSeparator
2) Change L&F to GTK using Menu "Look And Feel"
3) Click on button "Serialize Separator"
4) It will throw Exception in console
5) Now try serializing in someother look and feel it will
   give message "Successfully serialized Separator" on console
Tested on Tiger b30
Following is the exception message when serializing JSeparator under GTK
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Failed serializing javax.swing.JSeparator
java.io.NotSerializableException: javax.swing.plaf.synth.SynthSeparatorUI
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1072)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1366)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1338)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1281)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1070)
at java.io.ObjectOutputStream.defaultWriteFields(ObjectOutputStream.java:1366)
at java.io.ObjectOutputStream.defaultWriteObject(ObjectOutputStream.java:380)
at javax.swing.JComponent.writeObject(JComponent.java:5191)
at sun.reflect.GeneratedMethodAccessor40.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:489)
at java.io.ObjectStreamClass.invokeWriteObject(ObjectStreamClass.java:902)
at java.io.ObjectOutputStream.writeSerialData(ObjectOutputStream.java:1330)
at java.io.ObjectOutputStream.writeOrdinaryObject(ObjectOutputStream.java:1281)
at java.io.ObjectOutputStream.writeObject0(ObjectOutputStream.java:1070)
at java.io.ObjectOutputStream.writeObject(ObjectOutputStream.java:291)
at SerializeTest.serializeObject(SerializeTest.java:152)
at SerializeTest.main(SerializeTest.java:140)