teamcity-server-log4j.xml

  <appender name="ROLL.HIPCHAT.NOTIFIER" class="jetbrains.buildServer.util.TCRollingFileAppender">
    <param name="file" value="${teamcity_logs}hipchat-notifier.log"/>
    <param name="maxBackupIndex" value="3"/>
    <!--REPLACE PREVIOUS LINE WITH UNCOMMENTED LINE TO STORE MORE LOGS-->
    <!-- <param name="maxBackupIndex" value="20"/> -->

    <layout class="org.apache.log4j.PatternLayout">
      <param name="ConversionPattern" value="%d - %-5p - %m %n"/>
    </layout>
  </appender>

  <category name="com.whatsthatlight.teamcity.hipchat">
   <!-- Set this to DEBUG to enable debug logging -->
   <priority value="DEBUG"/>
    <appender-ref ref="ROLL.HIPCHAT.NOTIFIER"/>
  </category>