I agree with Julie. My other piece of advice is to be positive. Focus on what you do know and your strengths. As a recruiter I find that many people I prep before an interview tend to tell me everthing they don't know. I always explain it is best to focus on what you do know and your ability to learn and be resourceful with the tasks you are less familiar with. I have seen many great candidates talk themselves out of a position because of this. The interviewer can only see what is written on the resume and it is up to you to fill them in on what you are comfortable with learning and your capability to pick up any new technologies. So many people have the background but may be missing on skill the employer is looking for and during the interview they focus on that one item, such as
EJB. It is frustrating for all parties to keep going through the interview process.
The online technical tests have their pros and cons. Each testing service is different. I tend to take a look at the whole picture when presenting a candidate. Your education, training, experience and references are important. I like to hear feedback on the tests as well. It is the only way I can assess the true value of the test.
Good luck on your job search and happy interviewing!