+1  A: 

The exception is caused by the fact that the class is not in your GWT RPC whitelist (list of classes which are serializable).

I am unable to see any import of the org.datanucleas.sco.backed.ArrayList in any of the example code you have given.

Check out this question for more info on GWT and JPA.

Syntax  2010-08-18 00:47:19

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