--- /usr/pkg/lib/ruby/1.8/webrick/httpproxy.rb	2008-06-06 17:05:24.000000000 +0900
+++ httpproxy.rb	2013-09-03 18:20:16.000000000 +0900
@@ -125,9 +125,24 @@
       end
 
       response = nil
-      begin
-        http = Net::HTTP.new(uri.host, uri.port, proxy_host, proxy_port)
-        http.start{
+      is_new_connection = false
+      http = req.instance_variable_get(:@keeped_http)
+      while not response
+        if not http
+          is_new_connection = true
+          http = Net::HTTP.new(uri.host, uri.port, proxy_host, proxy_port)
+          req.instance_variable_set(:@keeped_http, http) unless req.keep_alive?
+          http.start
+        end
+        case req.request_method
+        when "GET"
+        when "POST"
+        when "HEAD"
+        else
+          raise HTTPStatus::MethodNotAllowed,
+            "unsupported method `#{req.request_method}'."
+        end
+        begin
           if @config[:ProxyTimeout]
             ##################################   these issues are 
             http.open_timeout = 30   # secs  #   necessary (maybe bacause
@@ -138,20 +153,22 @@
           when "GET"  then response = http.get(path, header)
           when "POST" then response = http.post(path, req.body || "", header)
           when "HEAD" then response = http.head(path, header)
-          else
-            raise HTTPStatus::MethodNotAllowed,
-              "unsupported method `#{req.request_method}'."
           end
-        }
-      rescue => err
-        logger.debug("#{err.class}: #{err.message}")
-        raise HTTPStatus::ServiceUnavailable, err.message
+          http.finish unless req.keep_alive?
+        rescue => err
+          req.instance_variable_set(:@keeped_http, nil)
+          if is_new_connection
+            logger.debug("#{err.class}: #{err.message}")
+            raise HTTPStatus::ServiceUnavailable, err.message
+          end
+          http = nil
+        end
       end
   
-      # Persistent connction requirements are mysterious for me.
-      # So I will close the connection in every response.
-      res['proxy-connection'] = "close"
-      res['connection'] = "close"
+      unless req.keep_alive?
+        res['proxy-connection'] = "close"
+        res['connection'] = "close"
+      end
 
       # Convert Net::HTTP::HTTPResponse to WEBrick::HTTPProxy
       res.status = response.code.to_i