Estoy usando JPA 2.0. (EclipseLink 2.0.2)

Si una entidad contiene relaciones, por ejemplo:

@OneToMany(cascade = CascadeType.ALL, mappedBy = "userId")
private Collection<Blog> blogCollection;

Recibo el siguiente error cuando lo envío a través de RPC:

com.google.gwt.user.client.rpc.SerializationException: Type 'org.eclipse.persistence.indirection.IndirectList' was not included in the set of types which can be serialized by this SerializationPolicy or its Class object could not be loaded. For security purposes, this type will not be serialized.: instance = {[]}