Problem Serialize De-serialize: List of Objects that contain Abstract types !

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What steps will reproduce the problem?
1. classes Animals, Dog extends Animals, Cat extends Animals,
Box (with two fields Animals, String)

2. Create a list with Boxes and add Boxes with Dogs and Cats

3. Serialize and De-serialize and view the list

What is the expected output? What do you see instead?
Expected: A list with boxes with dogs and cats.
Instead: A list with boxes with animals.

What version of the product are you using? On what operating system?
Gson 2.2.4, Linux Mint 13 Maya

Please provide any additional information below.

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Original issue reported on code.google.com by `totolici...@gmail.com` on 9 Aug 2013 at 7:42