title: Log4net C#4.0 [(null)] in output
body: <p>When I use log4net for logging in .NET4.0 I use the following code</p>
  
  <p>LogManager declaration:</p>
  
  <pre><code>private static readonly ILog log = LogManager.GetLogger(System.Reflection.MethodBase.GetCurrentMethod().DeclaringType);
  </code></pre>
  
  <p>And when used in code:</p>
  
  <pre><code>log.Info("My info text");
  </code></pre>
  
  <p>This outputs the following to the log-file:</p>
  
  <pre><code>2013-10-01 14:41:11,010 [3] INFO  MyNamespace.MyClass [(null)] - My info text
  </code></pre>
  
  <p>I am wondering what the <b>[(null)]</b> means and how I can remove/change it?</p>
  
  <p>This is my config-file:</p>
  
  <pre><code>&lt;?xml version="1.0"?&gt;
  &lt;configuration&gt;
    &lt;configSections&gt;
      &lt;section name="log4net" type="log4net.Config.Log4NetConfigurationSectionHandler,Log4net"/&gt;
    &lt;/configSections&gt;
    &lt;startup&gt;
      &lt;supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/&gt;
    &lt;/startup&gt;
    &lt;log4net&gt;
      &lt;root&gt;
        &lt;level value="DEBUG" /&gt;
        &lt;appender-ref ref="LogFileAppender" /&gt;
      &lt;/root&gt;
      &lt;appender name="LogFileAppender" type="log4net.Appender.RollingFileAppender" &gt;
        &lt;param name="File" value="log-file.txt" /&gt;
        &lt;param name="AppendToFile" value="true" /&gt;
        &lt;rollingStyle value="Size" /&gt;
        &lt;maxSizeRollBackups value="10" /&gt;
        &lt;maximumFileSize value="10MB" /&gt;
        &lt;staticLogFileName value="true" /&gt;
        &lt;layout type="log4net.Layout.PatternLayout"&gt;
          &lt;param name="ConversionPattern" value="%date [%thread] %-5level %logger [%property{NDC}] - %message%newline" /&gt;
        &lt;/layout&gt;
      &lt;/appender&gt;
    &lt;/log4net&gt;
  &lt;/configuration&gt;
  </code></pre>