Full commons-logging implementation
Tomcat uses a package renamed commons-logging API implementation which is hardcoded to use the java.util.logging API. The commons-logging additional component builds a full fledged package renamed commons-logging implementation which can be used to replace the implementation provided with Tomcat.
Web Services support (JSR 109)
Tomcat provides factories for JSR 109 which may be used to resolve web services references. Place the generated catalina-ws.jar as well as jaxrpc.jar and wsdl4j.jar (or another implementation of JSR 109) in the Tomcat lib folder.
Users should be aware that wsdl4j.jar is licensed under CPL 1.0 and not the Apache License version 2.0.
JMX Remote Lifecycle Listener
The JMX protocol requires the JMX server (Tomcat in this instance) to listen on two network ports. One of these ports can be fixed via configuration but the second is selected randomly. This makes it difficult to use JMX through a firewall. The JMX Remote Lifecycle Listener allows both ports to be fixed, simplifying the process of connecting to JMX through a firewall. See the listeners page for usage instructions.