Jasig CAS - 404 code after successful service ticket validation - jboss

Question

We are currently trying to deploy CAS 4.0.1 on a JBoss EAP 6.3.0 server.
The login webflow was customised in order to redirect to a specific login form depending on the service calling CAS for authentication. Depending on these forms, we use specific authentication handlers, and a specific Credential model. Besides that, the configuration is rather standard.
At the moment, we are experiencing the following issue: when a user attempts to access a service secured by CAS, he is correctly redirected to the portal, and the expected login view is rendered ; upon successful login, the Service Ticket is delivered to the authentication filter on the service side (standard j_spring_cas_security_check), which then validates it successfully against CAS' ticket registry. We see in the logs that CAS is rendering the cas2ServiceSuccessView ; however, instead of delivering the expected XML response, the user is redirected to the login form.
We then confirmed that we were in fact getting a 404 error after the cas2ServiceSuccessView... Any idea what could trigger such behaviour/what we could have done wrong ?
Note that we are getting the same error regardless of how we call CAS for the ST validation: whether it is manually through /serviceValidate?ticket=ST-YYY&service=XXX, or via the /j_spring_cas_security_check on the service side...
Edit: we have the same behaviour running CAS on Tomcat 7.
Thanks in advance.
Below the debug logs that we are getting:
08:54:10,806 DEBUG [org.springframework.web.servlet.DispatcherServlet] (http-/0.0.0.0:8080-7) Last-Modified value for [/cas/serviceValidate] is: -1
08:54:10,809 INFO [org.perf4j.TimingLogger] (http-/0.0.0.0:8080-7) start[1433314450807] time[2] tag[VALIDATE_SERVICE_TICKET]
08:54:10,810 INFO [com.github.inspektr.audit.support.Slf4jLoggingAuditTrailManager] (http-/0.0.0.0:8080-7) Audit trail record BEGIN
=============================================================
WHO: audit:unknown
WHAT: ST-3-uecoOwdbdIn4bc2WvXfe-cas-test
ACTION: SERVICE_TICKET_VALIDATED
APPLICATION: CAS
WHEN: Wed Jun 03 08:54:10 CEST 2015
CLIENT IP ADDRESS: 127.0.0.1
SERVER IP ADDRESS: 127.0.0.1
=============================================================
08:54:10,810 DEBUG [org.springframework.validation.DataBinder] (http-/0.0.0.0:8080-7) DataBinder requires binding of required fields [renew]
08:54:10,811 DEBUG [org.springframework.web.servlet.DispatcherServlet] (http-/0.0.0.0:8080-7) Rendering view [org.springframework.web.servlet.view.InternalResourceView: name 'cas2ServiceSuccessView'; URL [/WEB-INF/view/jsp/cas2ServiceSuccessView.jsp]] in DispatcherServlet with name 'cas'
08:54:10,811 DEBUG [org.springframework.web.servlet.view.InternalResourceView] (http-/0.0.0.0:8080-7) Added model object 'assertion' of type [org.jasig.cas.validation.ImmutableAssertion] to request in view with name 'cas2ServiceSuccessView'
08:54:10,811 DEBUG [org.springframework.web.servlet.view.InternalResourceView] (http-/0.0.0.0:8080-7) Removed model object 'pgtIou' from request in view with name 'cas2ServiceSuccessView'
08:54:10,811 DEBUG [org.springframework.web.servlet.view.InternalResourceView] (http-/0.0.0.0:8080-7) Forwarding to resource [/WEB-INF/view/jsp/cas2ServiceSuccessView.jsp] in InternalResourceView 'cas2ServiceSuccessView'
08:54:10,812 DEBUG [org.springframework.web.servlet.DispatcherServlet] (http-/0.0.0.0:8080-7) Successfully completed request
08:54:10,814 DEBUG [org.springframework.web.servlet.DispatcherServlet] (http-/0.0.0.0:8080-7) DispatcherServlet with name 'cas' processing GET request for [/cas/login]
08:54:10,814 DEBUG [org.springframework.webflow.mvc.servlet.FlowHandlerMapping] (http-/0.0.0.0:8080-7) Mapping request with URI '/cas/login' to flow with id 'login'

Answer 1

In SpringSecurity 4.x, CasAuthenticationFilter's defaultFilterProcessesUrl path is changed.
So Change '/j_spring_cas_security_check' to '/login/cas' in Configuration.

Answer 2

... and of course, the cause was rather silly: somehow (I have to look at our merge/git history), the viewResolver bean defined in cas-servlet.xml did not have a basenames property set.