# File lib/cookiejar/cookie_validation.rb, line 189
    def self.determine_cookie_domain request_uri, cookie_domain
      uri = to_uri request_uri
      domain = to_domain cookie_domain
    
      if domain == nil || domain.empty?
        domain = effective_host uri.host
      else
        domain = domain.downcase
        if domain =~ IPADDR || domain.start_with?('.')
          domain
        else
          ".#{domain}" 
        end
      end
    end