merge revision(s) 28302:
* ext/dl/lib/dl.rb: don't require when already loaded.
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@28304 b2dd03c8-39d4-4d8f-98ff-823fe69b080e
merge revision(s) 28302:
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@28304 b2dd03c8-39d4-4d8f-98ff-823fe69b080e