This is how I got cocoon 2.1 installed on top of tomcat 4.1 (on windows):
- unzip cocoon 2.1
- from the unzipped directory: "build clean webapp"
- install tomcat (i used the .exe installer)
- stop tomcat if it is running
- move the webapp directory in your cocoon-2.1/build directory to "C:\Program Files\Apache Group\Tomcat 4.1\webapps" (you don't want to copy this, trust me), and rename the webapp directory to "cocoon".
start tomcat and point browser to "http://127.0.0.1:8080"
- click on "Tomcat Manager" and enter your login and password provided during the tomcat install
- you should see the "cocoon" directory listed - click on the "start" url next to it (it takes some time here for the browser to come back with a reply page)
- click on the cocoon url itself, and you should be getting to the cocoon page
Instead of copying the webapp directory you can just build a WAR by using "build war" and move this WAR into Tomcat's webapps directory.