Why are case objects serializable and case classes not?

Question

I am playing with this example http://scala.sygneca.com/code/remoteactors to learn how remote actors work in Scala (2.8.0). In particular I slightly modified how the messages se

Answer 1

@serializable case class Foo

I was also surprised that case objects were serializable per default.

Edit: After reading the exception properly I suspect that:

You're trying to send the generated companion object of the case class over the wire, instead of an instance of the case class.