class Rake::Application

def rake_require(file_name, paths=$LOAD_PATH, loaded=$")

for *.rake files in addition to *.rb files.
Similar to the regular Ruby +require+ command, but will check 
def rake_require(file_name, paths=$LOAD_PATH, loaded=$")
  fn = file_name + ".rake"
  return false if loaded.include?(fn)
  paths.each do |path|
    full_path = File.join(path, fn)
    if File.exist?(full_path)
      Rake.load_rakefile(full_path)
      loaded << fn
      return true
    end
  end
  fail LoadError, "Can't find #{file_name}"
end