The fault code of the exception. For servers based on this library, this
will always be 0. (If there are predefined error codes, they should be in
the XML-RPC spec.)
linkedException
java.lang.Throwable linkedException
If the transport was able to catch a remote exception
(as is the case, if the local transport is used or if extensions
are enabled and the server returned a serialized exception),
then this field contains the trapped exception.