EJB

Geronimo embeds OpenEJB as its EJB container, so there's a lot of good info at http://www.openejb.org/ that's also relevant to Geronimo, for example http://www.openejb.org/geronimo.html and http://openejb.codehaus.org/hello-world.html .

Geronimo's build process depends on downloading a copy of openejb from some site somewhere, and sometimes geronimo and openejb change simultaneously in ways that need to be closely coordinated. In that case you'll want to build openejb from source so that geronimo's build process can use your local openejb.

openejb's web site points to old source code, but newer code seems to be located at:

  cvs -d :pserver:anonymous@cvs.openejb.codehaus.org:/home/projects/openejb/scm login
  (no password)
  cvs -d :pserver:anonymous@cvs.openejb.codehaus.org:/home/projects/openejb/scm 

Build openejb first, then geronimo.