Point of failure: https://github.com/wildfly/jboss-negotiation/blob/master/jboss-negotiation-net/src/main/java/org/jboss/security/negotiation/net/SPNEGOSocket.java#L127

Socket in mentioned versions log error and allow connection to be up. This is a cause of hangup in case of proxy lookup( atleast in EAP5 - JBPAPP-10748 )

Code should terminate connection and throw exception upstream, in case login/logout failure.