diff --git a/paramiko/hostkeys.py b/paramiko/hostkeys.py
index 015b3ba..a7f9b43 100644
--- a/paramiko/hostkeys.py
+++ b/paramiko/hostkeys.py
@@ -365,7 +365,7 @@ class HostKeys (MutableMapping):
             salt = base64.decodestring(b(salt))
         assert len(salt) == SHA.digest_size
         hmac = HMAC.HMAC(salt, b(hostname), SHA).digest()
-        hostkey = '|1|%s|%s' % (base64.encodestring(salt), base64.encodestring(hmac))
+        hostkey = '|1|%s|%s' % (u(base64.encodestring(salt)), u(base64.encodestring(hmac)))
         return hostkey.replace('\n', '')
     hash_host = staticmethod(hash_host)
 
diff --git a/paramiko/transport.py b/paramiko/transport.py
index 101fe17..c679a98 100644
--- a/paramiko/transport.py
+++ b/paramiko/transport.py
@@ -1747,8 +1747,8 @@ class Transport (threading.Thread):
         m.add_list(self._preferred_macs)
         m.add_list(self._preferred_compression)
         m.add_list(self._preferred_compression)
-        m.add_string('')
-        m.add_string('')
+        m.add_string(bytes())
+        m.add_string(bytes())
         m.add_boolean(False)
         m.add_int(0)
         # save a copy for later (needed to compute a hash)
@@ -1948,7 +1948,7 @@ class Transport (threading.Thread):
 
     def _parse_disconnect(self, m):
         code = m.get_int()
-        desc = m.get_string()
+        desc = m.get_text()
         self._log(INFO, 'Disconnect (code %d): %s' % (code, desc))
 
     def _parse_global_request(self, m):
diff --git a/tests/test_transport.py b/tests/test_transport.py
index 69fdbbb..ccd44e4 100644
--- a/tests/test_transport.py
+++ b/tests/test_transport.py
@@ -33,7 +33,7 @@ from paramiko import Transport, SecurityOptions, ServerInterface, RSAKey, DSSKey
     SSHException, BadAuthenticationType, InteractiveQuery, ChannelException
 from paramiko import AUTH_FAILED, AUTH_PARTIALLY_SUCCESSFUL, AUTH_SUCCESSFUL
 from paramiko import OPEN_SUCCEEDED, OPEN_FAILED_ADMINISTRATIVELY_PROHIBITED
-from paramiko.common import MSG_KEXINIT, MSG_CHANNEL_WINDOW_ADJUST
+from paramiko.common import MSG_KEXINIT, MSG_CHANNEL_WINDOW_ADJUST, b
 from paramiko.message import Message
 from tests.loop import LoopSocket
 from tests.util import ParamikoTest, test_path
@@ -162,7 +162,7 @@ class TransportTest(ParamikoTest):
         self.tc.H = unhexlify('0C8307CDE6856FF30BA93684EB0F04C2520E9ED3')
         self.tc.session_id = self.tc.H
         key = self.tc._compute_key('C', 32)
-        self.assertEquals('207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995',
+        self.assertEquals(b('207E66594CA87C44ECCBA3B3CD39FDDB378E6FDB0F97C54B2AA0CFBF900CD995'),
                           hexlify(key).upper())
 
     def test_3_simple(self):