PAC4J: clientName: null in 5.0.x ; while cas.authn.pac4j.autoRedirect=true works in CAS 510

[RJ]

The default redirection/authentication through PAC4J works fine with cas.authn.pac4j.autoRedirec=true in 5.1.x.

How do we achieve the same redirection (or default auth through pac4j, instead of throwing the login form) in CAS 5.0.x. Logs indicate that it has tried to redirect but failed with an error below.

Where to put the client name ? append to the query string of the end application URL ?

2017-05-17 12:30:24,106 DEBUG [org.apereo.cas.support.pac4j.web.flow.ClientAction] - <clientName: null>
..
..

2017-05-17 12:30:24,580 DEBUG [org.springframework.webflow.execution.ActionExecutor] - <Finished executing org.apereo.cas.support.pac4j.web.flow.ClientAction@79e8f7ad; result = error>
2017-05-17 12:30:24,580 DEBUG [org.springframework.webflow.execution.ActionExecutor] - <Finished executing [EvaluateAction@59488eed expression = clientAction, resultExpression = [null]]; result = error>

Thanks!