I have experimented with this setup (on Windows), and it seems to work fine. I got it to install, and run, and was able to edit/save my files and use the SlickEdit Prefences. However, there are incompatibilities listed on eclipse.org when migrating a 3.7.x compatible plugin to a 4.2 (juno) compatible plugin...so I can't guarantee your safety. Basically, it should work...but it is certainly not an officially supported platfom. If you have troubles I'm still more than happy to help you out, there.
- Ryan