Today I passed the exam and I am pleased with the result. It took seven months of study, quite a long time you might think but work and travel from Monday to Friday takes at least 12 hours a day.
I used the Head First EJB book, and a very good one it is. What helps a lot is the style of writing, not to mention the fact that it focuses on what you need for the exam. I do have a grumble though: it does not cover everything you need. Although I can't remember the details, I'm sure that there was one question in the exam which wasn't in the book. And the book's final mock exam has a question or two not covered in the book.
Speaking of the final mock exam, I got 70% when I took it two days before the real exam, so it's somewhat harder than the real thing.
Here's how I studied. I read the entire book and did each chapter's mock exams in five months. Then I did the same thing again. I referred a lot to the EJB spec and to the DTD. I kept notes in a Word doc, with a lot of stuff pasted from Javaranch's EJB forum (thanks Kathy!) and some from the EJB spec and the DTD.
Apart from the book's mock exams, the only ones I did were those from EJBPlus. Despite some questions which are a bit difficult to understand and a few errors, I've found these exams to be valuable exam preparation (I also used their mocks for the SCWCD).
In case you are wondering why I did so few mocks, the reason is that I knew that I was weak in several areas, so I just concentrated on learning them rather than taking lots of mocks which would have depressingly comfirmed to me that I didn't know it well!
One of the things I really struggled with was having to memorise DD elements. Sadly, you need to do some of this as you can get an XML snippet and be asked questions along the lines of "Which element should be inserted at line x".
Oh, and do learn in detail all those tables entitled "Operations allowed in the methods of a XXX bean". Trust me, you will lose a lot of marks if you don't do this.
One of the really useful things you can do immediately before you start the exam is to the draw on the notepad your are provided with the life cycle diagrams and the exception hierarchies. Then, during the exam, you just refer to your drawings. You have to be thoroughly familiar with all of this, so it should not be a problem.
Roger, I wish you had failed! If you had, then we could have had the benefit in the forum of your many well-thought-through answers! Now, I'm afraid, you'll be on to bigger and better things, and the forum will miss you.