diff --git a/ChangeLog b/ChangeLog
index 2f91cfb178..dc8d8fdb2b 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+Tue Apr 13 19:54:29 2004  Minero Aoki  <aamine@loveruby.net>
+
+	* lib/net/http.rb: should not overwrite HTTP request header.
+	  [ruby-list:39543]
+
 Tue Apr 13 01:30:00 2004  Gavin Sinclair <gsinclair@soyabean.com.au>
 
 	* ext/iconv/iconv.c: RDoc documentation (from RD; nearly finished).
diff --git a/lib/net/http.rb b/lib/net/http.rb
index 1943894382..02cbaeb30f 100644
--- a/lib/net/http.rb
+++ b/lib/net/http.rb
@@ -819,7 +819,7 @@ module Net # :nodoc:
     def request(req, body = nil, &block)  # :yield: +response+
       unless started?
         start {
-          req['connection'] = 'close'
+          req['connection'] ||= 'close'
           return request(req, body, &block)
         }
       end
@@ -848,12 +848,12 @@ module Net # :nodoc:
         on_connect
       end
       if @seems_1_0_server
-        req['connection'] = 'close'
+        req['connection'] ||= 'close'
       end
       if not req.response_body_permitted? and @close_on_empty_response
-        req['connection'] = 'close'
+        req['connection'] ||= 'close'
       end
-      req['host'] = addr_port()
+      req['host'] ||= addr_port()
     end
 
     def end_transport(req, res)