So what?
The tablets don't support Opera out of the box. Neither Canola2 or Maemo Mapper.

http://wiki.evolvis.org/jalimo/index.php/Packages claims to have working packages for the NITs (so I'd guess it cannot be that hard to get it up and running, but I admit I haven't tried it yet - I'm at worK)
The OP asked for opera mini support and that isn't requirering full java (if you talk about the jre) anyway, it's using the mobile stuff (The Opera website is quite unspecific or I cannot find the details) below the "Java ME" brand.

In other words: Saying "It's not supported" is unproven and not helpful. It might work. Pointing out limitations (no full jre) is fine, but claiming that no java support exists/works is crap, imo.

Back on topic: I'd try the Opera forums (checking the exact requirements of Opera Mini) and returning with that information to the jalimo project (Does that work already).
Faster/more pratical approach: Install jalimo and give it a try.