[Alexbt]

I would think that something built in Java would be more likely to work in OS X x86.

Shall I assume you know about the installer problems and did the Force Quit trick? It worked fine for me in the PPC 10.4.3.

EDIT: Totally miswrote the version of OS X I use. Fixed now. Silly me.

 

[Alexbt]

Then it should simply be a matter of when it was compiled and what it was compiled with. From what Apple is telling (and showing us), building Universal Binaries to run on EITHER processor flavor of OS X is as simple as checking off a box in the xCode development system.

Of course, I could be way off base. I'm by no means a programmer.