JDBC 7.3 dev (Java 2 SDK 1.4.0)

Hello,
  I have simple table with column ID and values '4' in this.
I user 7.3 beta1 (from cvs 05.09.2002) and autocommit off in postgresql.conf.
Next program don't work .
I am tried with compiled postgresql.jar form CVS and with
pg73b1jdbc3.jar from 05.09.2002 on jdbc.postgresql.org

What is wrong ?

regards
Haris Peco
import java.io.*;
import java.sql.*;
import java.text.*;

public class PrepStatTest
{
    Connection db;
    String stat="DELETE FROM org_ban WHERE \"id\" = ?";
    String delid = "4";
    public PrepStatTest() throws ClassNotFoundException, FileNotFoundException,
IOException, SQLException
    {
        Class.forName("org.postgresql.Driver");
        db = DriverManager.getConnection("jdbc:postgresql://spnew/snpe", "snpe",
"snpe");
        PreparedStatement st = db.prepareStatement(stat);
            st.setString(1, delid);
            int rowsDeleted = st.executeUpdate();
        System.out.println("Rows deleted " + rowsDeleted);
        db.commit();
        st.close();
        db.close();
    }

    public static void main(String args[])
    {
        try
        {
            PrepStatTest test = new PrepStatTest();
        }
        catch (Exception ex)
        {
            System.err.println("Exception caught.\n" + ex);
            ex.printStackTrace();
        }
    }
}