There is no way to refer to catalina home when specifying the filename of a logback valve.
What I would like to do is something like:
<Valve className="ch.qos.logback.access.tomcat.LogbackValve"
filename="${catalina.home}/conf/logback-access-test.xml"
/>
The only way for now is to specify an absolute path, which is not very convenient.
The system properties in the filename should be expanded in LogbackValve.start().