Index: django/http/__init__.py
===================================================================
--- django/http/__init__.py	(revision 5637)
+++ django/http/__init__.py	(working copy)
@@ -114,7 +114,7 @@
             self.encoding = encoding
         self._mutable = True
         for key, value in parse_qsl((query_string or ''), True): # keep_blank_values=True
-            self.appendlist(force_unicode(key, errors='replace'), force_unicode(value, errors='replace'))
+            self.appendlist(force_unicode(key, errors='replace', encoding=self.encoding), force_unicode(value, errors='replace', encoding=self.encoding))
         self._mutable = mutable
 
     def _assert_mutable(self):