Is "xmlns:log4j" a required attribute of the <log4j:configuration> tag?

Question

I see a bunch of sample log4j configurations that contain xmlns:log4j="http://jakarta.apache.org/log4j/" in the <log4j:configuration> tag, is this attribute required? What does having this attribute in my configuration do for me?

Example:

<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
    <appender name="infoLogsFile" class="org.apache.log4j.RollingFileAppender">
        <param name="File" value="MyApplication.log"/>     
        <layout class="org.apache.log4j.PatternLayout"> 
            <param name="ConversionPattern" value="%d %-5p [%c] %m%n"/>
        </layout>
    </appender>
    <root> 
        <priority value ="DEBUG" /> 
        <appender-ref ref="infoLogsFile"/>
    </root>
</log4j:configuration>

Could I do this instead?

<log4j:configuration>
    <appender name="infoLogsFile" class="org.apache.log4j.RollingFileAppender">
        <param name="File" value="MyApplication.log"/>     
        <layout class="org.apache.log4j.PatternLayout"> 
            <param name="ConversionPattern" value="%d %-5p [%c] %m%n"/>
        </layout>
    </appender>
    <root> 
        <priority value ="DEBUG" /> 
        <appender-ref ref="infoLogsFile"/>
    </root>
</log4j:configuration>

Answer 1

The xmlns attribute specifies that elements prepended with log4j are defined by the schema referenced by that URL. Log4J does not actually perform schema validation before attempting to parse the configuration file, so it is not actually required.