Dear Varun,
At present there is no exam simulator for IBM 484 exam. We do have a product for IBM 483 exam and are working for 484 simulator. But It will be released sometime in October only.
I'll suggest you take help from some of the good J2EE books, take related J2EE mock exams (like
SCEA 1, SCWCD and now SCBCD). I am sure there are few common/overlapping areas.
Best wishes,
Pradeep