My question about "the future" is what the plan or goal for making xml-apis "match" what ever is in a particular version of JRE's?

I know in 1.3, they sure didn't, in 1.4, they were close, but not quite, and there were differences between IBM's and Sun's (not sure about others).

And ... not sure about 1.5 ... maybe they match exactly?

So, my question is, is there a real efffort to be sure they match exactly for any particular future generation of JRE's, or,
is it a deliberate plan to allow your selves the flexibility to differ from current JRE's, so you can, if desired, get a "head start" ,
so to speak, on new specs?

Again, any insights welcome.