代码在执行：beginrc就提示下列异常，是哪里配置存在问题？

         NutTxDao tx= new NutTxDao(dao).setDebug(true);
          tx.beginRC();  

[DEBUG]-[Thread: http-bio-8080-exec-3]-[org.nutz.dao.impl.NutTxDao.begin()]: begin level=2 id=v2d8h7rqa8j92ok1mmq9g4o1uk
java.lang.AbstractMethodError: oracle.jdbc.driver.T4CConnection.setSavepoint()Ljava/sql/Savepoint;
	at com.alibaba.druid.pool.DruidPooledConnection.setSavepoint(DruidPooledConnection.java:979)
	at org.nutz.dao.impl.NutTxDao.setSavepoint(NutTxDao.java:179)
	at org.nutz.dao.impl.NutTxDao.begin(NutTxDao.java:121)