Serialisation bug with abstract classes

[Daniel Bonniot]

>replacing non-working code by other not-yet working (known as work in
>progress) is imo much better then leave known broken code. this shows
>that someone is working on it.
>  
>
100% agreed. That's why I said it was completely fine. At the end, I was 
commenting about the hypothetical situation where working code would be 
knowingly replaced by non-working code. Sorry if it was not clear.

Daniel