From Storable:

> Returned value: A LIST "($serialized, $ref1, $ref2,
> ...)" where $serialized is the serialized form to be
> used, and the optional $ref1, $ref2, etc... are extra
> references that you wish to let the Storable engine
> serialize.

> At deserialization time, you will be given back the
> same LIST, but all the extra references will be
> pointing into the deserialized structure.

So basically you need to return values to be serialized furthur. I'm not sure how exactly what they want, but then I'm not the one doing what your doing.