In this installment of Mastering Grails, series author Scott Davis puts to rest any qualms about Grails' readiness for the enterprise. You'll see how to use Grails with enterprise-caliber libraries including the Java(tm) Management Extensions (JMX), Spring, and log4j.
http://www.ibm.com/developerworks/web/library/j-grails12168/index.html?ca=dgr-twtrGrails-JMXdth-WD&S_TACT=105AGY83&S_CMP=TWDW
