Javaranch helped me a lot to prepare for this exam. I followed some old threads in javaranch regarding IBM 399. It's my pleasure if I get a chance to help other ranchers.
I have gone through the following books.
1. Websphere infor center for IBM 399(development Guide is very useful) 2. JSR 168 specification 3. Had 10 months of experience with portal and portlet development in RAD 4. studied some articles in IBM site 5. gone through some mock exams questions in Javaranch.
That's all I studied.
This exam is not that much tough as I expected. I just prepared for 2 weeks...4 hrs a day.