If you try to gzip all the text that is on the page, you get 44kB of data. You could possibly go below with some different compression algorithm, but not very much.
Opera Mini compression will be visible more likely on some more advanced pages with CSS, JS, images etc. On the page provided, there's simply not much that can be compressed.
I am fully aware that there is no way for a user to port an app that runs on Blackberry somewhere else, if not for some compatibility problems then Blackberry's strong security and encryption features stand against it. But it means that Opera could make a such a port with much less effort needed than a port of a native app would imply....
Btw. my Blackberry Q10 can do both: Android and native apps, and both could be Java..., and so far I have found no way to tell what exactly runs there... My old Samsung would indicate a running JRE with an icon, but the BB doesn't.