The dcm4chee tool sounds like a user provisioning tool to manage user/roles using a GUI.
The FedSSO Administration tool is actually a tool to manage the Federation Server component of the system.
Typical usecases will be, Real-time management of a Federation of partner sites, Adding/Removing partner sites in a federation, Managing Trust configuration of the Federation using Certificates etc.
Currently this has to be done via xml based configuration.
The requirements for this tool are not finalized yet.
Having said that, once development on the tool begins, I surely don't mind if you would like to contribute to the task. Your experience with JSF, SEAM, EJB3 would really come in handy.
Will keep you posted.