Thanks Samuel, I had about 3 weeks to study -fulltime- for this exam (being between projects), and I had not a lot of experience with the material.
Because of the deadline, I just sticked to the HF book which I think is a great study guide! I hope the HF EJB is like that too.
Forget about all the specifications, you really don't need them... unless you have plenty of time and enjoy reading them.
So I read the book twice and played with almost all code examples on my Tomcat server. I recommend NOT to use an IDE but just a plain text editor and code everything (java/jsp/xml) from scratch. That really makes it stick.
I took a lot of those Enthuware test, most of the time i scored about 75-80%. I did the final mock exam of HF once, but a bit too early ->70%