1 files changed, 3 insertions, 1 deletions
diff --git a/lib/net/http.rb b/lib/net/http.rb
index cc0a0b20dc..fac9a0beb1 100644
--- a/lib/net/http.rb
+++ b/lib/net/http.rb
@@ -987,7 +987,9 @@ module Net   #:nodoc:
       res = nil
       if HAVE_ZLIB
         unless  initheader.keys.any?{|k| k.downcase == "accept-encoding"}
-          initheader["accept-encoding"] = "gzip;q=1.0,deflate;q=0.6,identity;q=0.3"
+          initheader = initheader.merge({
+            "accept-encoding" => "gzip;q=1.0,deflate;q=0.6,identity;q=0.3"
+          })
           @compression = true
         end
       end