Hibernate version: 3.0.5

What I'm trying to do
I'm currently trying to map a legacy schema that I can't change. One of it's quirks is that it has several one-to-one relationships between one particular table, which I've mapped as an entity-type, and other tables which should be mapped as value-types (the primary keys are the same... don't ask me why they aren't in the same table, I don't know). These other tables really should be mapped as value-types because that's what makes sense semantically and I don't want to have to manually assign the natively generated primary key ID from the entity-type object to all the related objects which I think I would have to do if these other tables were mapped as entity-types.

Apology in advance
Now, I'm sure there's a way to do this, I apologise for asking, but I can't find what it is from the reference manual or the tutorial etc.

Options I've considered
The tag would work if the value types were in the same table as the entity type. But the tag doesn't seem to have a attribute for components from other tables.

A mapping would work using its attribute and the tag, only it's a one-to-one relationship, not a one-to-many.

Final plea
Is there any way to do what I'm trying to do?
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