log4j in grails : how to log into file?

I have this log4j configuration in my grails config.groovy ``` log4j = { error 'org.codehaus.groovy.grails.web.servlet', // controllers 'org.codehaus.groovy.grails.web.pages' // GSP warn 'org.mortbay.log' appenders { rollingFile name:'infoLog', file:'info.log', threshold: org.apache.log4j.Level.INFO, maxFileSize:1024 rollingFile name:'warnLog', file:'warn.log', threshold: org.apache.log4j.Level.WARN, maxFileSize:1024 rollingFile name:'errorLog', file:'error.log', threshold: org.apache.log4j.Level.ERROR, maxFileSize:1024 rollingFile name:'custom', file:'custom.log', maxFileSize:1024 } root { info 'infoLog','warnLog','errorLog','custom', stdout error() additivity = true } } ``` the infoLog,warnLog and errorLog was from the previous question ... they were working well. now I add new RollingFile wit name "custom" ... I tried to log from my controller and service using log.info("something .... ${obj}"); but it seems that message was not inserted into custom.log, do I need to add something to the configuration ? thank you !!