jdbc driver test

Hello

I have some code here to test a jdbc driver. Unfortionally I get a
NoClassDefFoundError. Here my code:

import java.sql.*;
import java.util.*;

public class DriverTest{
    public DriverTest(String driverClazz)
        throws ClassNotFoundException, SQLException {
        Class.forName(driverClazz);
  }

    public void info() throws SQLException {
        Enumeration e = DriverManager.getDrivers();
        System.out.println("Available drivers: ");
        while (e.hasMoreElements()) {
            Driver driver = (Driver) e.nextElement();
            System.out.println("Driver: " + driver.getClass().getName());
            System.out.println("Major version: " + driver.getMajorVersion());
            System.out.println("Minor version: " + driver.getMinorVersion());
            System.out.println("JDBC compliant: " + driver.jdbcCompliant());
    }
}

public static void main( String args[] ) throws Exception{
    if (args.length != 1) {
        System.out.println("usage: java DriverTest <DriverClazz>");
     }else{
        DriverTest dt = new DriverTest(args[0]);
        dt.info();
        }
}
}

This is what I do at shell (one line):
/usr/local/jdk1.6.0/bin/java -cp /path/to/postgersql-8.2-504.jdbc4.jar
DriverTest org.postgresql.Driver

I've tested this code a while ago on a Windows machine and with an oracle
driver, that worked fine. Hope somenone can help.

Thx