default gems of JRuby (especially jruby openssl)

JRuby comes with jruby-openssl as default gem and as default gem it is not part of bundle from Bundler and can cause problems. workaround is to explicitly add jruby-openssl to the Gemfile.

this is true for all default gems of JRuby using declared jars - currently it is jruby-openssl and jruby-readline (for coming JRuby-9000).