It is stored in the JSF ViewRoot attributes.
I also just thought about it.
Where has the server been switched to the client?
(Where does isClientSideConversations=true become it?)
Well, the UIViewRoot is the container for all controls on the Page and its the root element of the component tree.
However I actually wanted to know where the data is physically stored. I looked into some JSF books and found that client-state-saving puts the state into the rendered markup that is sent to the client, usually by using a large hidden html-input-field.
So, Seam puts the state information into the JSF ViewRoot Container and then delegates the responsibility for state-saving to JSF, and JSF is from that point on fully responsible for state-saving, is that correct?