This is related to
DDC-258. The issue seems to be fixed with regular column types (string, int, etc) but the same issue has cropped up when we have a OneToOne relationship in two child classes that share the same property name. I have modified the DDC258TestCase class to demonstrate the error.
To summarize: two classes that inherit from the same class happen to have a property with the same name. Both of them are oneToOne relationships. Querying for the objects, one object type (depending on discriminatorMap order) will be hydrate correctly but the other will always be null.