facebook-csharp-sdk/simple-json — pull request #48 by niemyjski (2014-03-04 15:34:50+00:00)
Title: Added unit test that breaks deserialization.

I believe the fix is inside of this method: public static Type[] GetGenericTypeArguments(Type type). The SettingsDictionary inherits from dictionary but doesn't have any generic type arguments. The base type would need to be checked.