Encrypting serialized Attribute

Hi,

I'd like to encrypt the content of a serialized attribute with rails built in serialize declaration. Unfortunately, using the before_save and after_find callbacks for encryption does not work in this case, because they are called before serialization and after deserialization.

Is there a way to implement custom callbacks like after_serialize and before_deserialize or any other recommended way of implementing encryption of serialized attributes?

Many thanks

Sam