in general, this can be controlled using a LogManager that can either be a class you want to use, or a properties file, it's specified using a system property .... the java logging documentation explains all of htis...
http://java.sun.com/j2se/1.5.0/docs/guide/logging/overview.html#1.8 But a lot of "enterprise" servlet containers have their own way to specifying what logging configuration options you want it to be using when it starts up the individual webapps. -Hoss
