When using threadify to create a multi-threaded script where a class uses the Java/Ruby integration layer and where imports are package imports such as:
And that class only gets instantiated inside the thread block, the following warning is displayed at start up for a number of classes that are loaded:
/usr/local/lib/jruby-1.3.0/lib/ruby/site_ruby/1.8/builtin/javasupport/core_ext/module.rb:27 warning: already initialized constant HttpHost
Where HttpHost may be a variety of class names.
I showed this to Charles tonight at RubyConf 2009, and he said he thought it could be fixed inside the JRuby code.