This distribution can be found on our downloads page listed as pentaho_j2ee_deployments.
This is also a good starting place if you are attempting to deploy to an application server not listed. All of the Pentaho files you will need exist in this package; all you will need to do is write your own Ant target, and add the configuration files necessary for your environment.
Our primary application server testing ground has been JBoss 4.2.1. The Pentaho community and the development team would greatly appreciate any feedback - whether it is problems faced or just to let us know you had a successful deployment - regarding deployments to other application servers. Please use the discussion forum at http://forums.pentaho.org to share your experience.