Now a from submitted via POST that also has a query string
will contain both FieldStorage and MiniFieldStorage items.

Fixes #1817.
diff --git a/Lib/cgi.py b/Lib/cgi.py
index 8760f96..561f5ad 100755
--- a/Lib/cgi.py
+++ b/Lib/cgi.py
@@ -456,6 +456,7 @@
         self.strict_parsing = strict_parsing
         if 'REQUEST_METHOD' in environ:
             method = environ['REQUEST_METHOD'].upper()
+        self.qs_on_post = None
         if method == 'GET' or method == 'HEAD':
             if 'QUERY_STRING' in environ:
                 qs = environ['QUERY_STRING']
@@ -474,6 +475,8 @@
                 headers['content-type'] = "application/x-www-form-urlencoded"
             if 'CONTENT_TYPE' in environ:
                 headers['content-type'] = environ['CONTENT_TYPE']
+            if 'QUERY_STRING' in environ:
+                self.qs_on_post = environ['QUERY_STRING']
             if 'CONTENT_LENGTH' in environ:
                 headers['content-length'] = environ['CONTENT_LENGTH']
         self.fp = fp or sys.stdin
@@ -631,6 +634,8 @@
     def read_urlencoded(self):
         """Internal: read data in query string format."""
         qs = self.fp.read(self.length)
+        if self.qs_on_post:
+            qs += '&' + self.qs_on_post
         self.list = list = []
         for key, value in parse_qsl(qs, self.keep_blank_values,
                                     self.strict_parsing):
@@ -645,6 +650,12 @@
         if not valid_boundary(ib):
             raise ValueError, 'Invalid boundary in multipart form: %r' % (ib,)
         self.list = []
+        if self.qs_on_post:
+            for key, value in parse_qsl(self.qs_on_post, self.keep_blank_values,
+                                        self.strict_parsing):
+                self.list.append(MiniFieldStorage(key, value))
+            FieldStorageClass = None
+
         klass = self.FieldStorageClass or self.__class__
         part = klass(self.fp, {}, ib,
                      environ, keep_blank_values, strict_parsing)