JPA-style positional param was not an integral ordinal

My JPA named native query:

 @NamedNativeQuery(
   name = "getFailure",
   query = "SELECT * " +
   "FROM INTERFACE_FAILURES " +
   "WHERE server_id = ?1" +
   "AND interface_name = ?2" +
   "AND date_time = TO_DATE(?3, 'dd/MM/yyyy hh:mi:ss PM') ",
   resultClass = InterfaceFailure.class
 )

called as follows:

   Query query = entityManager.createNamedQuery("getFailure")
   .setParameter(1, serverId)
   .setParameter(2, interfaceId)
   .setParameter(3, dateTime);

   if(query.getResultList().size() > 0) {
     failure = (InterfaceFailure)query.getSingleResult();   
   }


results in the following:

15:54:33,438 ERROR [org.hibernate.impl.SessionFactoryImpl] Error in named query: getFailure: org.hibernate.QueryException: JPA-style positional param was not an integral ordinal
 at org.hibernate.engine.query.ParameterParser.parse(ParameterParser.java:111) [:3.6.0.Final]
 at org.hibernate.loader.custom.sql.SQLQueryParser.substituteParams(SQLQueryParser.java:290) [:3.6.0.Final]
...


The solution, which google did not help with at all, hence my post:

 @NamedNativeQuery(
   name = "getFailure",
   query = "SELECT * " +
   "FROM INTERFACE_FAILURES " +
   "WHERE server_id = (?1)" +
   "AND interface_name = (?2)" +
   "AND date_time = TO_DATE(?3, 'dd/MM/yyyy hh:mi:ss PM') ",
   resultClass = InterfaceFailure.class
 )


Add brackets around the integral positional parameters.