Originally posted by Ulf Dittmer:
With all due respect to the interviewer: That's one of the stupidest interview questions I've heard in a long time. The answer to that can most likely be gotten in a minute by perusing Google or the vendor web site. Memorizing that fact tells you next to nothing about the applicant.
Maybe he is trying to see what server you have experience with? If you know this off the top of your head, you've either worked with WebSphere (or thought to pre-memorize it.) I agree there are questions better suited to find this out though.
Anyway:
WAS 5 - up to
Java 1.4
WAS 6 - up to Java 5