diff --git a/CHANGES b/CHANGES
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,13 @@
+* 3000.11.6 (10 November 2025)
+
+  - Add 'Accept: application/xml' header to requests.  Thanks to Jens
+    Petersen for the patch.
+
 * 3000.11.5.1 (29 July 2024)
 
   - Support GHC 9.10 and fix warnings
+
+  - r1 (4 June 2025): support GHC 9.12
 
 * 3000.11.5 (17 March 2023)
 
diff --git a/Network/XmlRpc/Client.hs b/Network/XmlRpc/Client.hs
--- a/Network/XmlRpc/Client.hs
+++ b/Network/XmlRpc/Client.hs
@@ -54,7 +54,8 @@
                                              getStatusMessage, http,
                                              inputStreamBody, openConnection,
                                              openConnectionSSL, receiveResponse,
-                                             sendRequest, setAuthorizationBasic,
+                                             sendRequest, setAccept,
+                                             setAuthorizationBasic,
                                              setContentLength, setContentType,
                                              setHeader)
 import           OpenSSL
@@ -209,6 +210,7 @@
     http POST (BS.pack $ uriPath uri)
     setContentType "text/xml"
     setContentLength len
+    setAccept "application/xml"
 
     case parseUserInfo auth of
       (Just user, Just pass) -> setAuthorizationBasic (BS.pack user) (BS.pack pass)
diff --git a/haxr.cabal b/haxr.cabal
--- a/haxr.cabal
+++ b/haxr.cabal
@@ -1,5 +1,5 @@
 Name: haxr
-Version: 3000.11.5.1
+Version: 3000.11.6
 Cabal-version: >=1.10
 Build-type: Simple
 Copyright: Bjorn Bringert, 2003-2006
@@ -22,7 +22,7 @@
         examples/test_client.hs       examples/test_server.hs       examples/time-xmlrpc-com.hs
         examples/validate.hs          examples/Makefile
 Bug-reports: https://github.com/byorgey/haxr/issues
-Tested-with: GHC ==8.4.4 || ==8.6.5 || ==8.8.4 || ==8.10.7 || ==9.0.2 || ==9.2.8 || ==9.4.8 || ==9.6.6 || ==9.8.2 || ==9.10.1
+Tested-with: GHC ==8.4.4 || ==8.6.5 || ==8.8.4 || ==8.10.7 || ==9.0.2 || ==9.2.8 || ==9.4.8 || ==9.6.7 || ==9.8.4 || ==9.10.2 || ==9.12.2
 
 Source-repository head
   type:     git
@@ -33,7 +33,7 @@
    default: True
 
 Library
-  Build-depends: base >= 4.9 && < 4.21,
+  Build-depends: base >= 4.9 && < 4.22,
                  base-compat >= 0.8 && < 0.15,
                  mtl < 2.4,
                  mtl-compat,