code: protected Collection<X509CertSelector> getIssuerSelectors(byte[] subjectDN) {
  		X509CertSelector caSelector = new X509CertSelector();
          caSelector.setBasicConstraints(0);
          try {
              caSelector.setSubject(subjectDN);
          } catch (IOException e) {
              // shut up
          }
          
  		return Arrays.asList(caSelector);
  	}
docs: {@inheritDoc}