When we have
class A
{
    ...
}
class B extends A
{
    ...
}
and we define MetaData as
<class name="A">
    <inheritance>
        <discriminator strategy="value-map"/>
    </inheritance>
</class>
<class name="B">
    <inheritance>
        <discriminator value="B"/>
    </inheritance>
</class>

The inheritance strategy chosen internally for B is "new-table" which is wrong by JDO2 spec - should be "superclass-table"