public byte[] export() throws GSSException {
   // Defaults to null to match old behavior
   byte[] result = null;
   // Only allow context export from native provider since JGSS
   // still has not defined its own interprocess token format
   if (mechCtxt.isTransferable() && mechCtxt.getProvider().getName().equals("SunNativeGSS")) {
     result = mechCtxt.export();
   }
   return result;
 }
 public boolean isTransferable() throws GSSException {
   if (mechCtxt != null) return mechCtxt.isTransferable();
   else return false;
 }