identity.login() repeated a successful login should throw an exception

Good morning guys, I'm not sure if this is a issue on PicketLink or at TODO demo. After user's registration and login, any user will be accepted at http://localhost:8080/todo/login.html

Scenario: http://github.com/picketlink/TODO

To reproduce the issue:

1 - Register a user
2 - Login with this user
3 - Return back to the login screen http://localhost:8080/todo/login.html
4 - Input any data and try to login

For more details, read the issue reported by Sebastien: http://aerogear-dev.1069024.n5.nabble.com/aerogear-dev-AeroGear-M8-Staging-releases-tp1583p1588.html