Someone found that distauth of Opensso cannot recieve session notifications from opensso server. My investigation showed that a new property "com.sun.identity.client.notification.url" was not set in AMConfig.properties of the distauth. This property is new to Opensso, somehow it was not there by default. If you want your opensso client to receive notifications from the session service, policy service and UM on the server, you need to add it.
See more details on DocTeger's blog