No extra configuration is needed. If log4j.xml or log4j.properties is present in the classpath, it is picked up and logs are directed to the specified appender(s). I found http://docs.codehaus.org/display/JETTY/Maven+Jetty+Plugin#MavenJettyPlugin-Logging overtly complicated and unnecessary. The logs can be redirected to a file by using a suitable appender in log4j.xml:
<appender name="FILE" class="org.apache.log4j.RollingFileAppender"> <param name="File" value="./target/dmsweb_log_file.log" /> <param name="Append" value="false" > <param name="MaxBackupIndex" value="1" > <param name="MaxFileSize" value="500KB" > <layout class="org.apache.log4j.PatternLayout"> <param name="ConversionPattern" value="%d [%t] %-5p %c - %m%n"> </layout> </appender>