Alan Kay points out that "Unlike Java, [Squeak] runs bit-identical on every machine -- we invented this 20 years ago". The wikipedia page mentions this also:
Squeak is available for many platforms, and programs produced on one platform run bit-identical on all other platforms.
Since machines with different instruction sets obviously can't run bit-identical programs natively, what does it mean when one says that Squeak runs bit-identical programs on different machines, in a way that Java doesn't?
I'm under the impression that compiled Java classes runs identically on any machine on any JVM, is that not so?