Magnus K Karlsson writes Effective Unit Testing EJB 3.0 with OpenEJB.
As you state quite well, Mangus, many people have had a bad experience with EJB 2.1 and although simpler EJB 3.0 is not so easily testable without a container. Unless of course you use an embedded EJB container like OpenEJB.
We greatly appreciate blog posts like yours as many people try and fail with a few approaches before finally finding OpenEJB. So many more people don't even look for a solution. Blog posts like yours go a long way in helping to get the word out.