In theory - if the J2EE specification is to be believed - it should be possible to take an application that runs on an older version of a J2EE Servlet container (like Apache Tomcat) and install it on a newer version without breaking anything. Real life, as is often the case, is not that simple. In this presentation, Mark Thomas will work though the potential pitfalls when upgrading your Tomcat server - both from changes to how Tomcat is configured and from 'improvements' in the specifications. For each potential pitfall Mark will explain how to avoid it and how to work-around it should you come across it.