If you've played with JRuby and have strong opinions on how Ruby and Java should integrate, that'd be a big plus.
This is usually a full-time job, with no problem with entry-level folk. But I'll bet we'd be happy to have an intern as well. I'll ask the guys at work :-)
It's a small programming team (about 8 full-time), but a very stable non-startup company. You won't get rich, but you'll have a lot of say in what we're doing.