# File httpd/lib/symbiosis/config_files/apache.rb, line 85
      def enable(fn = nil, force = false)
        #
        # Take the filename and and replace available with enabled if no
        # filename is given.
        #
        fn = self.filename.sub("sites-available","sites-enabled") if fn.nil?

        #
        # Do nothing if we're already enabled.
        #
        return if self.enabled?(fn)

        #
        # Clobber any files in the way, if the force flag is set.
        #
        if force and File.exists?(fn)
          File.unlink(fn)
        end

        #
        # If the file is still there after disabling, raise an error
        #
        raise Errno::EEXIST, fn if File.exists?(fn)

        #
        # Symlink away!
        #
        File.symlink(self.filename, fn)

        nil
      end