Hello,
I just tried the example given for variable substitution in the FAQ with logback 1.0.0:
http://logback.qos.ch/faq.html#sharedConfiguration
And it seems the "context.reset();" line is not in the right place.

If I use the same code as in the example, I got this (I added a few lines of code at the end to print the filename that should be changed after doConfigure()):
--BEGIN CODE--
LoggerContext context = (LoggerContext) LoggerFactory.getILoggerFactory();
        // context.reset(); // This works!
        // property of the LoggerContext
        context.putProperty("application-name", "killerapp");
        JoranConfigurator jc = new JoranConfigurator();
        jc.setContext(context);
        context.reset(); // override default configuration. This does not work (no variable substitution)!
        try {
            jc.doConfigure(Test.class.getResourceAsStream("/logback.xml"));
        } catch (JoranException e1) {
            throw new RuntimeException(e1);
        }

        Appender<ILoggingEvent> appender = context.getLogger("mylogger").getAppender("FILE");
        String filename = ((RollingFileAppender<ILoggingEvent>) appender).getFile();
        System.out.println("filename = " + filename);
--END CODE--

--OUTPUT--
filename = d:/users/logs/application-name_IS_UNDEFINED_error.log
--END OUTPUT--

Now, if I uncomment line 2: "// context.reset(); // This works!"
and comment out " context.reset(); // override default configuration...", I get what I want:
--OUTPUT--
filename = d:/users/logs/killerapp_error.log
--END OUTPUT--

In short, it makes a more sense and it works if context.reset() is done before setting the property. Otherwise, I guess the property map is cleared with the reset if done after.

Am I correct? In which case, the FAQ should be fixed accordingly

Thanks.