I recall that 1.4.0 was open to all, but after 1.4.1 (I think there was some change in agreements) IBM restricted their support policies.

There is more detail on the SDK here:
http://www-106.ibm.com/developerwork...HW03&S_CMP=ZHP
(This includes a note about renewing expired certificates - as long as you have an IBM product from my interpretation)

There's no longer much on the JRE info page, and at the last paragraph you are referred to Sun for current JRE support:
http://www-106.ibm.com/developerwork.../jre-info.html