public Collection findCertificatesBySubjectAndIssuer(Admin admin, String subjectDN, String issuer) throws RemoteException;
public Collection findCertificatesBySubjectAndIssuer(Admin admin, String subjectDN, String issuerDN) throws RemoteException;
    public Collection findCertificatesBySubjectAndIssuer(Admin admin, String subjectDN, String issuer) throws RemoteException;