// a null response is 99% likely to be due to a marshalling problem - we throw a NSE, this needs to be changed when
// JGroups supports http://jira.jboss.com/jira/browse/JGRP-193
// the serialization problem could be on the remote end and this is why we cannot catch this above, when marshalling.
if (retval == null)
throw new NotSerializableException("RpcDispatcher returned a null. This is most often caused by args for "
+ command.getClass().getSimpleName() + " not being serializable.");
if (supportReplay) {
boolean replay = false;
Vector<Address> ignorers = new Vector<Address>();