Looks like we can't use every willy-nilly.
Through trial and error, I find this is the way.

To avoid crashy cycles on startup.
Added -binary-version option.
scala 2.10.0
Auto-add Opts.resolver.sonatypeSnapshots on SNAPSHOTs
Update to sbt 0.12.2
Clean up output generation / logging.
Update launcher jar to 0.12.2
Merge commit 'refs/pull/38/head'
OpenJDK 6 and 7 by default have UseConcMarkSweepGC disabled. Thus, setting just CMSClassUnloadingEnabled will not work as intended. This can be verified by examining the OpenJDK 6 and 7 source: /hotspot/src/share/vm/runtime/globals.hpp
Merge pull request #40 from rockymadden/master

OpenJDK 6 and 7 issues with CMSClassUnloadingEnabled being set without UseConcMarkSweepGC