problem: configuration files will be restored after call new Configuration

[Wangda.Tan]

Hi All,

Environment:
Hadoop 0.20.205 (0.20.204 also have this problem)
Mac OS 10.6
Java 1.6

I meet a very weird problem, when I make some changes of core-site.xml or other 
configuration files in HADOOP_CONF, if I run a program with (new 
Configuration), the changed config files will restored to xxx.xml.template:

How to reproduce:

Make a little change to core-site.xml:
<configuration>
    <property>
        <name>test.val</name>
        <value>test.val</value>
    </property>
</configuration>

Run a program with the following main method:
public class TestConf {
  public static void main(String[] args) {
    Configuration conf = new Configuration();
    System.out.println(conf.get("test.val"));
  }
}

This program will print "null", and core-site.xml will restore to:
<configuration>
</configuration>

Can anyone point me to this problem?
--
Regards,
Wangda