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();
}
}
}