链接数据库时报错！

报错：
log4j:WARN No appenders could be found for logger (org.hibernate.cfg.Environment).
log4j:WARN Please initialize the log4j system properly.
Exception in thread "main" org.hibernate.exception.GenericJDBCException: Cannot open connection
at org.hibernate.exception.SQLStateConverter.handledNonSpecificException(SQLStateConverter.java:126)
at org.hibernate.exception.SQLStateConverter.convert(SQLStateConverter.java:114)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:66)
at org.hibernate.exception.JDBCExceptionHelper.convert(JDBCExceptionHelper.java:52)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:449)
at org.hibernate.jdbc.ConnectionManager.getConnection(ConnectionManager.java:167)
at org.hibernate.jdbc.JDBCContext.connection(JDBCContext.java:142)
at org.hibernate.transaction.JDBCTransaction.begin(JDBCTransaction.java:85)
at org.hibernate.impl.SessionImpl.beginTransaction(SessionImpl.java:1353)
at cn.itcast.hibernate.Base.main(Base.java:21)
Caused by: java.sql.SQLException: 用户 'sa' 登录失败。
at net.sourceforge.jtds.jdbc.SQLDiagnostic.addDiagnostic(SQLDiagnostic.java:365)
at net.sourceforge.jtds.jdbc.TdsCore.tdsErrorToken(TdsCore.java:2781)
at net.sourceforge.jtds.jdbc.TdsCore.nextToken(TdsCore.java:2224)
at net.sourceforge.jtds.jdbc.TdsCore.login(TdsCore.java:599)
at net.sourceforge.jtds.jdbc.ConnectionJDBC2.<init>(ConnectionJDBC2.java:331)
at net.sourceforge.jtds.jdbc.ConnectionJDBC3.<init>(ConnectionJDBC3.java:50)
at net.sourceforge.jtds.jdbc.Driver.connect(Driver.java:178)
at java.sql.DriverManager.getConnection(Unknown Source)
at java.sql.DriverManager.getConnection(Unknown Source)
at org.hibernate.connection.DriverManagerConnectionProvider.getConnection(DriverManagerConnectionProvider.java:133)
at org.hibernate.jdbc.ConnectionManager.openConnection(ConnectionManager.java:446)
... 5 more我的配置文件是
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd"><hibernate-configuration>
<session-factory>
<property name="hibernate.connection.url">jdbc:jtds:sqlserver://localhost:1433/test</property>
<property name="hibernate.connection.driver_class">net.sourceforge.jtds.jdbc.Driver</property>
<property name="hibernate.connection.username">sa</property>
<property name="hibernate.connection.password">sa</property>
<property name="hibernate.dialect">org.hibernate.dialect.SQLServerDialect</property>
<property name="hibernate.show_sql">true</property>
                  <property name="hibernate.show_sql">true</property>
--><property name="hbm2ddl.auto">create</property>
<mapping resource="cn/itcast/hibernate/domain/User.hbm.xml"/>
</session-factory>
</hibernate-configuration>
我的jdbc驱动jar包已经导入，并且我可以用sa登录sqlserver 
public static void main(String[] args) {
Configuration cfg=new Configuration();
cfg.configure();
SessionFactory sf=cfg.buildSessionFactory(); Session s=sf.openSession();
Transaction tx=s.beginTransaction();
    User user=new User();
    user.setBirthday(new Date());
    user.setName("name");
    s.save(user);
    tx.commit();
    s.close();
    System.out.println("end");
}
这个方法报错了那位大侠帮帮我啊？