It would be better if you appear for SCJP 6 certification exam as it is the latest one. Moreover, there are only slight difference between in the objectives of SCJP 5 and SCJP 6 certification exams so it will not take much time.
The objectives with modifications are API Contents, Collections/Generics and Fundamentals.
For further information please visit the following link:
SCJP6
Regards,
Usha Atwal
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