Thank Clark for your immediate answer.
I have doubt because there are very differences between version 1.4 and 1.5 (tiger)
if we adds also the difference with the version 1.6 it seems strange that is sufficient only
the SCJP 1.6 upgrade exam.
Hovewer if you confirm me this you spur me to take the SCJP 1.6
Another question : which book is more suitable for to take the SCJP 1.6 upgrade exam ?