diff --git a/Lib/email/message.py b/Lib/email/message.py
index 2713bc5..922617a 100644
--- a/Lib/email/message.py
+++ b/Lib/email/message.py
@@ -48,9 +48,9 @@
 def _splitparam(param):
     # Split header parameters.  BAW: this may be too simple.  It isn't
     # strictly RFC 2045 (section 5.1) compliant, but it catches most headers
-    # found in the wild.  We may eventually need a full fledged parser
-    # eventually.
-    a, sep, b = param.partition(';')
+    # found in the wild.  We may eventually need a full fledged parser.
+    # RDM: we might have a Header here; for now just stringify it.
+    a, sep, b = str(param).partition(';')
     if not sep:
         return a.strip(), None
     return a.strip(), b.strip()
@@ -90,6 +90,8 @@
         return param
 
 def _parseparam(s):
+    # RDM This might be a Header, so for now stringify it.
+    s = ';' + str(s)
     plist = []
     while s[:1] == ';':
         s = s[1:]
@@ -240,7 +242,8 @@
         if i is not None and not isinstance(self._payload, list):
             raise TypeError('Expected list, got %s' % type(self._payload))
         payload = self._payload
-        cte = self.get('content-transfer-encoding', '').lower()
+        # cte might be a Header, so for now stringify it.
+        cte = str(self.get('content-transfer-encoding', '')).lower()
         # payload may be bytes here.
         if isinstance(payload, str):
             if _has_surrogates(payload):
@@ -561,7 +564,7 @@
         if value is missing:
             return failobj
         params = []
-        for p in _parseparam(';' + value):
+        for p in _parseparam(value):
             try:
                 name, val = p.split('=', 1)
                 name = name.strip()
diff --git a/Lib/email/test/test_email.py b/Lib/email/test/test_email.py
index dcb2e95..9f64e09 100644
--- a/Lib/email/test/test_email.py
+++ b/Lib/email/test/test_email.py
@@ -2995,6 +2995,58 @@
                               ['foo@bar.com',
                                'g\uFFFD\uFFFDst'])
 
+    def test_get_content_type_with_8bit(self):
+        msg = email.message_from_bytes(textwrap.dedent("""\
+            Content-Type: text/pl\xA7in; charset=utf-8
+            """).encode('latin-1'))
+        self.assertEqual(msg.get_content_type(), "text/pl\uFFFDin")
+        self.assertEqual(msg.get_content_maintype(), "text")
+        self.assertEqual(msg.get_content_subtype(), "pl\uFFFDin")
+
+    def test_get_params_with_8bit(self):
+        msg = email.message_from_bytes(
+            'X-Header: foo=\xa7ne; b\xa7r=two; baz=three\n'.encode('latin-1'))
+        self.assertEqual(msg.get_params(header='x-header'),
+           [('foo', '\uFFFDne'), ('b\uFFFDr', 'two'), ('baz', 'three')])
+        self.assertEqual(msg.get_param('Foo', header='x-header'), '\uFFFdne')
+        # XXX: someday you might be able to get 'b\xa7r', for now you can't.
+        self.assertEqual(msg.get_param('b\xa7r', header='x-header'), None)
+
+    def test_get_rfc2231_params_with_8bit(self):
+        msg = email.message_from_bytes(textwrap.dedent("""\
+            Content-Type: text/plain; charset=us-ascii;
+             title*=us-ascii'en'This%20is%20not%20f\xa7n"""
+             ).encode('latin-1'))
+        self.assertEqual(msg.get_param('title'),
+            ('us-ascii', 'en', 'This is not f\uFFFDn'))
+
+    def test_set_rfc2231_params_with_8bit(self):
+        msg = email.message_from_bytes(textwrap.dedent("""\
+            Content-Type: text/plain; charset=us-ascii;
+             title*=us-ascii'en'This%20is%20not%20f\xa7n"""
+             ).encode('latin-1'))
+        msg.set_param('title', 'test')
+        self.assertEqual(msg.get_param('title'), 'test')
+
+    def test_del_rfc2231_params_with_8bit(self):
+        msg = email.message_from_bytes(textwrap.dedent("""\
+            Content-Type: text/plain; charset=us-ascii;
+             title*=us-ascii'en'This%20is%20not%20f\xa7n"""
+             ).encode('latin-1'))
+        msg.del_param('title')
+        self.assertEqual(msg.get_param('title'), None)
+        self.assertEqual(msg.get_content_maintype(), 'text')
+
+    def test_get_payload_with_8bit_cte_header(self):
+        msg = email.message_from_bytes(textwrap.dedent("""\
+            Content-Transfer-Encoding: b\xa7se64
+            Content-Type: text/plain; charset=latin-1
+
+            payload
+            """).encode('latin-1'))
+        self.assertEqual(msg.get_payload(), 'payload\n')
+        self.assertEqual(msg.get_payload(decode=True), b'payload\n')
+
     non_latin_bin_msg = textwrap.dedent("""\
         From: foo@bar.com
         To: báz