如何关闭Struts2的日志

各位：
我在log4j.properties配置文件中对Struts2的日志配置是：log4j.logger.com.opensymphony.xwork2=ERROR
这样关闭了大部分日志。可是还是有部分日志打印出。如下：
09:51:24,468 DEBUG InstantiatingNullHandler:84 - Entering nullPropertyValue [target=[com.opensymphony.xwork2.DefaultTextProvider@1b5f7e0], property=struts]
09:51:24,562 DEBUG InstantiatingNullHandler:84 - Entering nullPropertyValue [target=[com.opensymphony.xwork2.DefaultTextProvider@1b5f7e0], property=struts]
09:51:25,125 DEBUG XWorkConverter:84 - Property: null
09:51:25,125 DEBUG XWorkConverter:84 - Class: com.opensymphony.xwork2.util.CompoundRoot
09:51:25,125 DEBUG XWorkConverter:84 - field-level type converter for property [null] = none found
09:51:25,125 DEBUG XWorkConverter:84 - global-level type converter for property [null] = none found
09:51:25,125 DEBUG XWorkConverter:84 - falling back to default type converter [com.opensymphony.xwork2.conversion.impl.XWorkBasicConverter@cbd575]

请问应如何关闭这些日志，在jboss服务器下不打印任何Struts2的日志？ --------------------编程问答-------------------- 同上。
无法屏蔽 struts2 自带的 com.opensymphony.xwork2.util.logging.commons.CommonsLogger 日志输出。
web 程序启动时，就会输出一次
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2011-11-18 17:08:12,400 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Parsing configuration file [struts-default.xml]
2011-11-18 17:08:12,618 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Parsing configuration file [struts-plugin.xml]
2011-11-18 17:08:12,806 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Unable to locate configuration files of the name struts/wbgo/wbgo400/struts-wbgo400.xml, skipping
2011-11-18 17:08:13,103 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Parsing configuration file [struts.xml]
2011-11-18 17:08:13,353 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Initializing Struts-Spring integration...
2011-11-18 17:08:13,353 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    Setting autowire strategy to name
2011-11-18 17:08:13,353 [INFO ][main] method:com.opensymphony.xwork2.util.logging.commons.CommonsLogger.info(CommonsLogger.java:31)
    ... initialized Struts-Spring integration successfully
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struts2 应该在属性文件中添加一个可以开启和关闭日志的功能。
--------------------编程问答-------------------- 看来，只有改源码了。 --------------------编程问答-------------------- 贴log4j配置 --------------------编程问答--------------------     <logger name="org.apache.struts2" additivity="false">
        <level value="WARN"/>
        <appender-ref ref="ConsoleLayout"/>
    </logger>
--------------------编程问答-------------------- 除

补充：Java ,  Web 开发