I am firing following query

Transaction tx3 = session.beginTransaction();
Query query3 = session.createSQLQuery("SELECT SYSTIMESTAMP FROM DUAL");
Object x = (Object)query3.uniqueResult(); //line 3
System.out.println(x);
tx3.commit();

while executing line 3 i am getting following error

exceptiontsorg.hibernate.MappingException: No Dialect mapping for JDBC type: -101

I am getting same exception with the following query also

/* String dateQuery = "select to_timestamp_tz( to_char(TO_DATE('19700101000000','YYYYMMDDHH24MISS') ,'mm/ddyyyy hh24:mi:ss'),'mm/ddyyyy hh24:mi:ss TZH:TZM')"+
"at time zone 'america/los_angeles' from dual";
Query dateQueryTZ = session.createSQLQuery(dateQuery);*/

Can any one tell me how to fix this and get the timestamp value.
Please tell me if any alternative are there for the above query.

Thanks in advance
Partha