Hi Avanti,
If I was in your place, I would make efforts to pass the SCJP 5 instead of SCJP 1.4
In opposite to what Arun said, there are a LOT of differences between
Java 1.4 and 1.5
For example, you can consider as deep differences from Java 1.4 to 1.5 :
Covariant Returns,
Wrapper classes (Autoboxing and unboxing),
Enhanced For Loop,
StringBuilder vs StringBuffer,
Collections and Generics,
API contents,
As well as many other topics.
Both exams (1.4 and 1.5) are VERY different, for example, Java IO API Contents is charged in the new exam but shift and bitwise operators are not. In opposite to what is charged in the SCJP 1.4 exam.
So, in face of all deep changes that follow the new Java version and SCJP exam, I think that would be a good challenge for you try to pass the new one.