Wouldn't these sorts of issues be solved more easily if the Gemfile listed specific versions of the gem dependencies? I don't like the idea of allowing a Rails app to just download whatever is the most recent version of a gem for this exact reason.
You can specify gem versions in a Gemfile. It's a good idea when you lock down an app and don't plan to update it regularly. This blog post is concerned with the larger issue of starting new projects and finding that certain integrations require specific tweaks that are often not well known and may be temporary. Rails and its gem ecosystem evolves constantly.