Later, your path through learning J2EE will go much more smoothly. Even though some of the concepts you get to practice, while working the SCJD, are not directly related to J2EE components, nearly everything is indirectly related. Now I that I am studying for the SCWCD, I am soooo glad I took the SCJD first.
For example, because of having to learn Threads and synchronization so much more thoroughly, while building my SCJD project, than I did to pass the SCJP exam, I am now much more aware of the implications Threading and synchronization has on Servlets. Furthermore, after the SCJP, I knew nothing about RMI, but I had to at least learn the basics for the SCJD, so I am much more prepared for EJBs down the line than I would be otherwise.
Take the SCJD now. Good Luck.
SCJP - 1.4
SCJD - (B&S) Used 1.5 And It Runs On Solaris10
SCWCD - Thanks to HFSJ!!