Its all up to you to decide. You can go ahead with SCWCD with out even taking SCJP. SCJP 1.5 or 6 will not be so tough for you as you have already taken 1.4.
So, why don't you quickly finish SCJP6 and come back to SCWCD?
Please be sure of what you are saying. You can't go for the web component exam unless you are a certified programmer.
In a nutshell, SCJP(any edition) is a pre-requisite if you want to got for SCWCD.
Well, about the version of programmer exam, it really doesn't matter, as you see Sun is very clear about that. You can go ahead for SCWCD even with your SCJP 1.4 certification.
But, at anytime it's better to be in touch with the latest technology and J2SE 1.5 was major revolution. Also, I heard some people mentioning that they encountered some J2SE 1.5 specific syntax in their SCWCD exam.
Anyway, over and above all things the fact is you can go for SCWCD with your current SCJP version. It's all uto you how you want to go ahead.
Hope that helps..!!
You guys haven't done this much, have ya? I suggest you study this tiny ad:
a bit of art, as a gift, that will fit in a stocking