add_explicit_path_to_config_gem.rb

## require in config/environment.rb before init starts
#require 'config/add_explicit_path_to_config_gem'
#Rails::Initializer.run do |config|
#config.gem 'my_gem', :version => '0.0.1', :explicit_path => "#{RAILS_ROOT}/vendor/local_gemfiles/my_gem-0.0.1.gem" #or
#config.gem 'my_gem', :version => '0.0.1', :explicit_path => "http://github.com/myname/myrepo/raw/master/mygem.gem" #or

module Rails
  class GemDependency < Gem::Dependency
    def initialize(name, options = {})
      require 'rubygems' unless Object.const_defined?(:Gem)

      if options[:requirement]
        req = options[:requirement]
      elsif options[:version]
        req = Gem::Requirement.create(options[:version])
      else
        req = Gem::Requirement.default
      end

      @lib      = options[:lib]
      @source   = options[:source]
      @loaded   = @frozen = @load_paths_added = false
      @explicit_path = options[:explicit_path]

      super(name, req)
    end
  
  private

    def install_command
      cmd = %w(install) << (@explicit_path || name)
      cmd << "--version" << %("#{requirement.to_s}") if requirement
      cmd << "--source"  << @source  if @source
      cmd
    end
  end
end