Valentin,
Thanks a lot.
Sonir,
Sorry for the delay in response ... but you know I had put away a lot of my responsibilities coz' of the exam preparation and I had a lot of catching up to do on the personal and work front. Anyway, coming over to your questions/queries, I will narrate my experience:
Firstly, do not get tensed at all. There's absolutely nothing to be gained by being tensed and nervous. In fact you will surely not do well in the exam if you let all these emotions to overcome you. Make it a practice to remain calm and composed under all circumstances. Its easy for me to say it now. But believe me, I was in the same shoes as you are now in. And I told to myself that being nervous and getting worked/tensed up is not getting me anywhere. So whenever I used to start feeling the tension, I would try to divert myself into something that made me forget about the entire stuff (for a short while of course), by watching my favorite show on TV or listening to music or a short walk in the park or even in silent prayer. So I would suggest something on those lines. But the important thing to remember is that you shouldn't lose your focus and let the tension work against you. In fact make it work FOR you. Good Luck on this front!
According to me, it is not sufficient to read just RHE. You can use this book (which I did) or Khalid Mughal's for the final 3 weeks of exam cram. But to get concepts clarified and get a grip of the fundamentals, you would need to study from other sources/books. I referred a lot to java.sun.com site and I also read couple of other authors before referring RHE (notably, Herbert Schildt's certification book and Deitel & Deitel's Complete Java 2 Reference). It is even more the case if you aren't working in the Java field, since a lot of fundas become clear only by extensive self coding or if you are already in the Java field working.
Once you feel you are confident about the concepts, then cram thru' RHE once and take the mock exams, specifically Marcus Green's (which is of pretty good standard compared to actual one) and gauge your performance. Then based on the weak points on the mock exam results, prepare more. I know its a lot to do and you have very less time on your hands. But this is what I did and I made sure I was doing decently good on all the important mock exams (I was averaging 80% and above in most of them) before I went ahead and purchased the voucher and set the date for the exam.
About the exam itself, the questions are on the expected lines based on the mock exams. I never had the time to take the more difficult mock exams like Barry Boone's and Khalid Mughal's. But in hindsight I feel I should've taken them and that way I would have been able to score better in the real exam. But one
word of caution !!! The real exam is not easy, but neither is it too difficult to pass. But to score above 85%, you must have done your homework thoroughly. There is surely scope for making mistakes in the exam questions since more than one choice seem to be the correct answer (for exactly one right answer) and other choices appear to be correct too (for multiple correct answers).
According to me all topics (i.e all 13 chapters in RHE) are equally important. Remember you are preparing not only to get certified, but also to be a future Java Developer/Architect. So do not omit any chapters if possible. Because this knowledge will surely come to use in future.
As far as my reaction to the questions, I was kinda glad that I took so many mock exams, because I had got used to the
pattern and I was able to finish the exam in about 1hr 10mins and used the rest of the time to revise. But remember however early you finish the exam, even on your second run thru' the questions, there is less chances of your making a drastic impact on the overall result. Because you either know or don't know. But make use of all the time at your disposal.
I hope I have been able to answer to your queries satisfactorily. Let me know if you need anything else.
Regards,
Venu
on the first attempt, although I scored only 62% 
(Yeah, just barely made it, I know). But nevertheless, a pass is a pass, and I am relieved that all my hardwork didn't go waste. 
My special thanks to all the guys at Javaranch who helped me in this success story, especially Maha Anna's resource page, Velmurugan's study notes, Marcus Green's Mock exams, etc.
