.well-known/openid-configuration returns Internal Server Error

Steps to reproduce:

1. Install and setup OpenAM, I used the nightly build war (2014-April-16).
2. Log in to OpenAM and create an OAuth 2.0 provider.
3. Access to http://openam.example.com:8080/openam/.well-known/openid-configuration .
   -> Internal Server Error message is shown: {"error":"Internal Server Error","error_description":"The server encountered an unexpected condition which prevented it from fulfilling the request"}

tomcat6/logs/catalina.out

2014/04/24 10:43:30 org.restlet.Restlet handle
Warn: Unable to start the Restlet
java.lang.NullPointerException
at org.forgerock.openam.WebFinger.createInboundRoot(WebFinger.java:50)
at org.restlet.Application.getInboundRoot(Application.java:270)
at org.restlet.engine.application.ApplicationHelper.start(ApplicationHelper.java:127)
at org.restlet.Application.start(Application.java:582)
at org.restlet.routing.Filter.start(Filter.java:274)
at org.restlet.Restlet.handle(Restlet.java:315)
at org.restlet.routing.Filter.handle(Filter.java:202)
at org.restlet.routing.Router.doHandle(Router.java:431)
at org.restlet.routing.Router.handle(Router.java:648)
at org.restlet.routing.Filter.doHandle(Filter.java:159)
at org.restlet.routing.Filter.handle(Filter.java:206)
at org.restlet.routing.Router.doHandle(Router.java:431)
at org.restlet.routing.Router.handle(Router.java:648)
at org.restlet.routing.Filter.doHandle(Filter.java:159)
at org.restlet.routing.Filter.handle(Filter.java:206)
at org.restlet.engine.CompositeHelper.handle(CompositeHelper.java:211)
at org.restlet.Component.handle(Component.java:392)
at org.restlet.Server.handle(Server.java:516)
at org.restlet.engine.ServerHelper.handle(ServerHelper.java:72)
at org.restlet.engine.adapter.HttpServerHelper.handle(HttpServerHelper.java:152)
at org.restlet.ext.servlet.ServerServlet.service(ServerServlet.java:1089)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.forgerock.openam.validation.ResponseValidationFilter.doFilter(ResponseValidationFilter.java:44)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at com.sun.identity.setup.AMSetupFilter.doFilter(AMSetupFilter.java:100)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:127)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
at org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
at org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
at org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
at java.lang.Thread.run(Thread.java:662)