diff --git a/paramiko/ber.py b/paramiko/ber.py
index 4aa788d..a12eed1 100644
--- a/paramiko/ber.py
+++ b/paramiko/ber.py
@@ -19,6 +19,8 @@
 from __future__ import absolute_import
 from paramiko import util
 
+import six
+
 
 class BERException (Exception):
     pass
@@ -112,7 +114,7 @@ class BER(object):
                 self.encode_tlv(1, '\xff')
             else:
                 self.encode_tlv(1, '\x00')
-        elif (type(x) is int) or (type(x) is long):
+        elif isinstance(x, six.integer_types):
             self.encode_tlv(2, util.deflate_long(x))
         elif type(x) is str:
             self.encode_tlv(4, x)
diff --git a/paramiko/dsskey.py b/paramiko/dsskey.py
index 5b3e642..9384ec0 100644
--- a/paramiko/dsskey.py
+++ b/paramiko/dsskey.py
@@ -20,6 +20,10 @@
 L{DSSKey}
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from Crypto.PublicKey import DSA
 from Crypto.Hash import SHA
 
diff --git a/paramiko/primes.py b/paramiko/primes.py
index 9ebfec1..c6a38b7 100644
--- a/paramiko/primes.py
+++ b/paramiko/primes.py
@@ -20,6 +20,9 @@
 Utility functions for dealing with primes.
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
 from Crypto.Util import number
 
 from paramiko import util
diff --git a/paramiko/rsakey.py b/paramiko/rsakey.py
index 1e2d8f9..c1c4b8d 100644
--- a/paramiko/rsakey.py
+++ b/paramiko/rsakey.py
@@ -20,6 +20,10 @@
 L{RSAKey}
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from Crypto.PublicKey import RSA
 from Crypto.Hash import SHA, MD5
 from Crypto.Cipher import DES3
diff --git a/paramiko/sftp_client.py b/paramiko/sftp_client.py
index 86b272a..07f5162 100644
--- a/paramiko/sftp_client.py
+++ b/paramiko/sftp_client.py
@@ -20,6 +20,10 @@
 Client-mode SFTP support.
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from binascii import hexlify
 import errno
 import os
diff --git a/paramiko/sftp_file.py b/paramiko/sftp_file.py
index 2274039..ae3c787 100644
--- a/paramiko/sftp_file.py
+++ b/paramiko/sftp_file.py
@@ -20,6 +20,10 @@
 L{SFTPFile}
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from binascii import hexlify
 from collections import deque
 import socket