JDBC连接SQL Server2000的问题

连接数据库的代码如下:
Class.forName("com.microsoft.jdbc.sqlserver.SQLServerDriver").newInstance();
System.out.println("SQL数据库驱动加载成功!");

String url = "jdbc:microsoft:sqlserver://localhost:1433;databasename=mydb";
String user = "sa";
String password = "";
try {
Connection conn = DriverManager.getConnection(url,user,password);
System.out.println("SQL数据库连接成功!");
} catch (SQLException e) {
System.out.println("SQL数据库连接不成功!");
e.printStackTrace();
}
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异常如下:
SQL数据库驱动加载成功!
java.sql.SQLException: [Microsoft][SQLServer 2000 Driver for JDBC]Error establishing socket.
at com.microsoft.jdbc.base.BaseExceptions.createException(Unknown Source)
at com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
at com.microsoft.jdbc.base.BaseExceptions.getException(Unknown Source)
at com.microsoft.jdbc.sqlserver.tds.TDSConnection.<init>(Unknown Source)
at com.microsoft.jdbc.sqlserver.SQLServerImplConnection.open(Unknown Source)
at com.microsoft.jdbc.base.BaseConnection.getNewImplConnection(Unknown Source)
at com.microsoft.jdbc.base.BaseConnection.open(Unknown Source)
at com.microsoft.jdbc.base.BaseDriver.connect(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at com.test.SQLDBAccess.getConnection(SQLDBAccess.java:30)
at com.test.SQLDBAccess.main(SQLDBAccess.java:46)
SQL数据库连接不成功!
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SQL server安装的时候设置的仅windows验证,后来改成SQL Server和Windows验证,并设置sa的密码为空,在查询分析器下用sa登录没问题!
后来在SQL下新建了一个账户aa,密码也是aa,结果在代码里连接出现同样的异常!

装一个sql server sp3或sp4补丁看看

windows下的jdbc补丁装过没有啊？？？