Thank you very much, it's working nicely now. My log4j.xml appender def'n now looks like. <!-- Custom logging for patent prior art database changes--> <appender name="PRIORART" class="org.jboss.logging.appender.DailyRollingFileAppender"> <param name="File" value="${jboss.server.home.dir}/log/priorart.log"/> <param name="Append" value="true"/> <param name="Threshold" value="INFO"/> <param name="DatePattern" value="'.'yyyy-MM"/> <layout class="org.apache.log4j.PatternLayout"> <param name="ConversionPattern" value="%d{MMM dd,yyyy HH:mm:ss} %-5p [%c{1}] %m%n"/> </layout> </appender> I guess I was having problems because there aren't any decent DailyRollingFileAppender examples that use a config.xml file in the archives, and the javadoc stuff seems to be for direct incorporation of log4j into .java files (not for a connector type architecture). I also looked in the log4j download for examples, and there aren't any DailyRollingFileAppender examples (others yes). The log4j.dtd is also not available via links in the documentation, which would have solved 75% of my problems, after you gave me the hints (which really helped). I didn't know which optional tags could or shouldn't be used, so it was trial and error after that. But persistence pays off in the end. I found DatePattern stuff within a poor example in JBoss and in javadoc (although not the proper syntax for xml files), and Append="true" versus "false" by experimentation. As you are probably aware, if you restart the server with Append = "false" the log is overwritten, if you haven't reached the rollover date criteria yet. These comments should be taken as suggestions and are not critical comments. With kindest regards, Chris Yoerg Hi, You need to use a DailyRollingFileAppender. You'll get the rollover and file naming (no overwriting). See the javadoc for org.apache.log4j.DailyRollingFileAppender and examples in the mailing list archives for this list. Unless I completely misunderstood your question? Yoav Shapira Millennium ChemInformatics