dev-lang/ruby-enterprise 1.8.7-2011.03 is currently in the tree but masked. This is because with USE=threads the thread-related tests crash the ruby process. This is a regression compared to previous ruby-enterprise versions. It does not appear to happen when ruby-enterprise is installed outside of portage, so the most likely cause is somewhere in the ebuild or the way portage handles the installation.
At this point we should be looking at 1.8.7-2012.02.
(In reply to comment #1) > At this point we should be looking at 1.8.7-2012.02. Which also crashes in the test suite: /callerforallthreads/test_caller_for_each_thread.rb:52: [BUG] Segmentation fault ruby 1.8.7 (2012-02-08 MBARI 8/0x6770 on patchlevel 358) [x86_64-linux], MBARI 0x6770, Ruby Enterprise Edition 2012.02
Package dev-lang/ruby-enterprise has been removed. See #453178.