I think this is a trade-off between having the token store based solely on the Cas `TicketRegistry`  and having spring-security-oauth handle the token storage for us (either through an in-memory hashmap implementation, or by having the user configure the token store himself inside `oauthConfiguration.xml`). If we are willing to allow a separate token store from the ticket registry it simplifies a ton of work, at least for the initial release of this enhancement.