Ok. I see the problem now. Loosening the dependencies allowed bundler to resolve versions that would allow twitter 5.0 to be included in the bundle. But in the process, introduces several other regressions. 

@sferik, what are your feelings on changing `twitter`'s dependency on `http_parser.rb` to `~0.6.0.beta.2`? That will allow it to be compatible with the latest `em-http-request` and `em-twitter`