Since uPortal requires Servlet 2.4 and JDK5 Tomcat 5.5 is the preferred choice for running uPortal. This is the servlet container included with the uPortal quickstart and is probably the most common of the containers listed here.
The build.xml has support for deploying to your Tomcat 5.5 or 6.0 installation. All you need to do is set the server.home property in build.properties to point to your tomcat installation. Then you can run "ant deploy-war" to deploy to tomcat. You will need to restart tomcat at least the first time. Reloading the context after that will work.
Tomcat 6.0 Notes
uPortal places libraries in CATALINA_BASE/shared/lib The default Tomcat 6.0 download does not enable libraries to be loaded from this directory. To resolve this you must edit CATALINA_BASE/conf/catalina.properties and change the line "shared.loader=" to "shared.loader=${catalina.base}/shared/classes,${catalina.base}/shared/lib/*.jar" . Don't forget to restart tomcat after applying this change.