重现：classNotFoundException

（在Eclipse中）
package ch2;

import java.sql.*;
//import com.mysql.jdbc.Driver;
public class TestConn {



public static void main(String[] args){
String username = "root";
String password = "kevoo";
Connection conn = null;
Statement stat = null;
ResultSet rs = null;

try{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/login",username,password);
stat = conn.createStatement();
rs = stat.executeQuery("select * from user_info");
int id = rs.getInt(1);
System.out.print(id);
}catch(Exception e){
e.printStackTrace();
}finally{
try{
rs.close();
stat.close();
conn.close();
}catch(Exception e){}

}


}
}


运行时提示java.lang.ClassNotFoundException: com.mysql.jdbc.Driver
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClassInternal(Unknown Source)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Unknown Source)
at ch2.TestConn.main(TestConn.java:17)


但我已经在项目的lib目录下加进了mysql-connector-java-5[1].0.0-beta-bin.jar包，并且也在项目属性－－>构建路径－－>库中添加了这个jar包。（mysql-connector-java-3.1.7-bin.jar也没有用！）


请高手帮忙了。。。