I recently encounter an exception in a servlet that run as standalone in Tomcat. The tomcat log did not give much help as far as what was going on. After two days of digging and help from Nuke@jboss.org. It turns out that the Logger object from log4j package is not serializable that cause exception when a method returns an object that contains the Logger object. My question is that should Jboss complain about this un-serialiable object before it returns object. If an exception was thrown and log at the Jboss server.log file then I may be able to find out the problem in one hour instant of two days.