Just wanted to say that the installers can be somewhat confusing.
The patch installer for 4.0.4 application server is actually a fullblown installer, that screws up the previous 4.0.4 install if installed on top of it. Starts getting error on startup etc...
Name of the file might have been confusing. It's not a point patch. It's a full blown installer with a few bug fixes. Specifically a critical ejb3 issue was fixed back then.
Please see http://labs.jboss.com/portal/jemsinstaller/downloads for the latest installer.