Java Database Connectivity (JDBC)

I am using

conn = Util.getConnection();
prepStmt = conn.prepareStatement(sql);


prepStmt.setLong(1, district);
prepStmt.setLong(2, elarPersonID);
prepStmt.setString(3, typeCode);
prepStmt.setString(4, durationCode);
prepStmt.setString(5, createdBy);
prepStmt.setString(6, updatedBy);
System.out.println("I am here at 2.");
prepStmt.executeUpdate(sql);


after printing I am here at 2. it gives following exception.I searched on google about this exception. It says that replace driver with new one.
But, I want to note here that rest of the application is working fine. I am just adding query ....and it's giving me exception.
so, i don't think driver problem. There might be different one.

Could you explain in detail?

java.sql.SQLException: ORA-03115: unsupported network datatype or representation

at oracle.jdbc.driver.DatabaseError.throwSqlException(DatabaseError.java:125)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:305)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:272)
at oracle.jdbc.driver.T4C8Oall.receive(T4C8Oall.java:626)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:185)
at oracle.jdbc.driver.T4CPreparedStatement.execute_for_rows(T4CPreparedStatement.java:633)
at oracle.jdbc.driver.OracleStatement.doExecuteWithTimeout(OracleStatement.java:1090)
at oracle.jdbc.driver.OracleStatement.executeUpdate(OracleStatement.java:1492)
at weblogic.jdbc.wrapper.Statement.executeUpdate(Statement.java:433)