Judges that do not support Java

I’ve noticed that szkopul.edu.pl does not actually support Java submissions. However, problems from that judge are still listed on usaco.guide when lang=java. Does anyone know where else Olympiad problems like those can be submitted? I checked on oj.uz but can’t seem to find many POI problems.

For anybody running into the same problem (lacking language support), try https://vjudge.net/