Amit's post I think already answers it:
Amit Ghorpade wrote:Probably the best thing to do is to check with Sun itself.
Since 1.5 is relatively new, one can expect the 1.4 to be continued for a considerable amount of time.
That said, why not opt for the newer version when there isn't big change in the objectives?
For the updated exam the best reference based on other posts is still
RMH book.
Just like in the older version of the exam.