I found a few bugs in those exams in jdiscuss. Some of my correct answers, it showed as incorrect. You can also try www.ejbcertificate.com and download a free trial from INESystems. It contains 5 exams with 70 ques. Worth taking it.
Are you sure you downloaded the right one. The trial ver I used had 5 mock exams with 70 ques . There were a total of 15 exams, but the rest 10 were inactive since it was the trial one. I searched my pc.. and got this link from history. Try it, but don't know whether this is the right one or not .... http://www.inesystems.com/download/tmp524t/INESystems_SCBCD_Install.exe