public ResponseStanzaContainer execute(Stanza stanza, ServerRuntimeContext serverRuntimeContext, boolean isOutboundStanza, SessionContext sessionContext, SessionStateHolder sessionStateHolder) {
XMLElementVerifier xmlElementVerifier = stanza.getVerifier();
boolean jabberNamespace = xmlElementVerifier.namespacePresent(NamespaceURIs.HTTP_ETHERX_JABBER_ORG_STREAMS);
boolean clientCall = xmlElementVerifier.namespacePresent(NamespaceURIs.JABBER_CLIENT);
boolean serverCall = xmlElementVerifier.namespacePresent(NamespaceURIs.JABBER_SERVER);
if (clientCall && serverCall) serverCall = false; // silently ignore ambiguous attributes
if (serverCall) sessionContext.setServerToServer(); else sessionContext.setClientToServer();
if (sessionStateHolder.getState() != SessionState.INITIATED &&