Ceki, Ralph,
I did try the TurboFilter as suggested, however, something which I probably didn't make explicitly clear in my original post was that I configure a ThresholdFilter within each of my appenders to filter out messages below a certain level - as I said previously, its likely that the application I'm working on will be configured only to log messages of WARN and above. For example:
<appender name="STDOUT" class="ch.qos.logback.core.ConsoleAppender">
<turboFilter class="ch.qos.logback.classic.turbo.MarkerFilter">
<Name>ALWAYSLOG</Name>
<Marker>ALWAYSLOG</Marker>
<OnMatch>ACCEPT</OnMatch>
</turboFilter>
<filter class="ch.qos.logback.classic.filter.ThresholdFilter">
<level>WARN</level>
</filter>
...
...
</appender>
Although the Marker turbofilter is ACCEPTing messages which contain the appropriate 'marker' as expected, the message will then get filtered out by the subsequent the Threshold filter - I suppose I could extend the standard Threshold filter to look for the presence of the marker and bypass normal threshold filtering in these cases... or did I misunderstand something?
Regards,
Shane