Fixture loads hierachical model incorrectlly

Below Class design will cause problems while loading yml file by Fixture:

public abstract Class Tag extends Model { ... }
public Class FunctionTag extends Tag { ... }

public abstract Class Post extends Model {
    @ManyToMany
    public Set<Tag> tags;
    ......
}
public Class Artical extends Post {
    ......
}

And we have below yml to initialize data:
FunctionTag(ft1):
    ......
Artical(a1):
    tags: [ft1]

Two problems here:
1. The "resolveDependencies" doesn't look into superClass to resolve relationships, so that the FunctionTag defined in yml file cannot be set to Post.tags.
2. After FunctionTag is persisted, the key which is put into "idCache" (e.g models.FunctionTag - ft1) is not the same with the key which generated by "resolveDependencies" method (e.g models.Tag - ft1).

Below is the proposed solution:
Old Code:
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line 135:
                       idCache.put(type + "-" + id, JPASupport.findKey(model));
line 173:
        for (Field field : type.getDeclaredFields()) { ...... }
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New Code:
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line 135:
                        while (!cType.equals(JPASupport.class)) {
                            idCache.put(cType.getName() + "-" + id, JPASupport.findKey(model));
                            cType = cType.getSuperclass();
                        } // This solution might not solve the problem as the yml definition has duplicated id between different
                          // inherited classes. And it will generate some useless key and grow the idCache size.
line 173:
        Set<Field> fields = new HashSet<Field>();
        Class clazz = type;
        while (!clazz.equals(JPASupport.class)) {
            Collections.addAll(fields, clazz.getDeclaredFields());
            clazz = clazz.getSuperclass();
        }
        for (Field field : fields) { ...... }
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