class Rake::ExtensionTask

def define_cross_platform_tasks(for_platform)
  if ruby_vers = ENV['RUBY_CC_VERSION']
    ruby_vers = ENV['RUBY_CC_VERSION'].split(':')
  else
    ruby_vers = [RUBY_VERSION]
  end
  multi = (ruby_vers.size > 1) ? true : false
  ruby_vers.each do |version|
    # save original lib_dir
    orig_lib_dir = @lib_dir
    # tweak lib directory only when targeting multiple versions
    if multi then
      version =~ /(\d+\.\d+)/
      @lib_dir = "#{@lib_dir}/#{$1}"
    end
    # Update cross compiled platform/version combinations
    @ruby_versions_per_platform[for_platform] << version
    define_cross_platform_tasks_with_version(for_platform, version)
    # restore lib_dir
    @lib_dir = orig_lib_dir
  end
end