diff --git a/.gitignore b/.gitignore
index 4b57895..3d537cd 100644
--- a/.gitignore
+++ b/.gitignore
@@ -5,3 +5,4 @@ dist/
 paramiko.egg-info/
 test.log
 docs/
+.idea/
\ No newline at end of file
diff --git a/paramiko/kex_group1.py b/paramiko/kex_group1.py
index 1386cf3..20b89b5 100644
--- a/paramiko/kex_group1.py
+++ b/paramiko/kex_group1.py
@@ -28,11 +28,14 @@ from paramiko import util
 from paramiko.message import Message
 from paramiko.ssh_exception import SSHException
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
 
 _MSG_KEXDH_INIT, _MSG_KEXDH_REPLY = range(30, 32)
 
 # draft-ietf-secsh-transport-09.txt, page 17
-P = 0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFFL
+P = long(0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF)
 G = 2
 
 
@@ -42,9 +45,9 @@ class KexGroup1(object):
 
     def __init__(self, transport):
         self.transport = transport
-        self.x = 0L
-        self.e = 0L
-        self.f = 0L
+        self.x = 0
+        self.e = 0
+        self.f = 0
 
     def start_kex(self):
         self._generate_x()
diff --git a/paramiko/message.py b/paramiko/message.py
index 47acc34..fb9e565 100644
--- a/paramiko/message.py
+++ b/paramiko/message.py
@@ -277,7 +277,7 @@ class Message (object):
         elif type(i) is int:
             return self.add_int(i)
         elif type(i) is long:
-            if i > 0xffffffffL:
+            if i > long(0xffffffff):
                 return self.add_mpint(i)
             else:
                 return self.add_int(i)
diff --git a/paramiko/packet.py b/paramiko/packet.py
index ad92733..df443bb 100644
--- a/paramiko/packet.py
+++ b/paramiko/packet.py
@@ -27,6 +27,10 @@ import struct
 import threading
 import time
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from paramiko.common import *
 from paramiko import util
 from paramiko.ssh_exception import SSHException, ProxyCommandFailure
@@ -94,8 +98,8 @@ class Packetizer (object):
         self.__mac_key_in = ''
         self.__compress_engine_out = None
         self.__compress_engine_in = None
-        self.__sequence_number_out = 0L
-        self.__sequence_number_in = 0L
+        self.__sequence_number_out = 0
+        self.__sequence_number_in = 0
 
         # lock around outbound writes (packet computation)
         self.__write_lock = threading.RLock()
@@ -315,7 +319,7 @@ class Packetizer (object):
             if self.__block_engine_out != None:
                 payload = struct.pack('>I', self.__sequence_number_out) + packet
                 out += compute_hmac(self.__mac_key_out, payload, self.__mac_engine_out)[:self.__mac_size_out]
-            self.__sequence_number_out = (self.__sequence_number_out + 1) & 0xffffffffL
+            self.__sequence_number_out = (self.__sequence_number_out + 1) & long(0xffffffff)
             self.write_all(out)
 
             self.__sent_bytes += len(out)
@@ -375,7 +379,7 @@ class Packetizer (object):
 
         msg = Message(payload[1:])
         msg.seqno = self.__sequence_number_in
-        self.__sequence_number_in = (self.__sequence_number_in + 1) & 0xffffffffL
+        self.__sequence_number_in = (self.__sequence_number_in + 1) & long(0xffffffff)
 
         # check for rekey
         raw_packet_size = packet_size + self.__mac_size_in + 4
diff --git a/paramiko/sftp_attr.py b/paramiko/sftp_attr.py
index 59a823b..d99de8b 100644
--- a/paramiko/sftp_attr.py
+++ b/paramiko/sftp_attr.py
@@ -16,6 +16,10 @@
 # along with Paramiko; if not, write to the Free Software Foundation, Inc.,
 # 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA.
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 import stat
 import time
 from paramiko.common import *
@@ -44,7 +48,7 @@ class SFTPAttributes (object):
     FLAG_UIDGID = 2
     FLAG_PERMISSIONS = 4
     FLAG_AMTIME = 8
-    FLAG_EXTENDED = 0x80000000L
+    FLAG_EXTENDED = long(0x80000000)
 
     def __init__(self):
         """
@@ -200,7 +204,7 @@ class SFTPAttributes (object):
         else:
             ks = '?---------'
         # compute display date
-        if (self.st_mtime is None) or (self.st_mtime == 0xffffffffL):
+        if (self.st_mtime is None) or (self.st_mtime == long(0xffffffff)):
             # shouldn't really happen
             datestr = '(unknown date)'
         else:
diff --git a/paramiko/transport.py b/paramiko/transport.py
index e37d931..ca35d53 100644
--- a/paramiko/transport.py
+++ b/paramiko/transport.py
@@ -25,10 +25,15 @@ import socket
 import string
 import struct
 import sys
+
 import threading
 import time
 import weakref
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 import paramiko
 from paramiko import util
 from paramiko.auth_handler import AuthHandler
@@ -374,7 +379,8 @@ class Transport (threading.Thread):
 
         @rtype: str
         """
-        out = '<paramiko.Transport at %s' % hex(long(id(self)) & 0xffffffffL)
+
+        out = '<paramiko.Transport at %s' % hex(long(id(self)) & long(0xffffffff))
         if not self.active:
             out += ' (unconnected)'
         else:
@@ -1549,9 +1555,9 @@ class Transport (threading.Thread):
         # active=True occurs before the thread is launched, to avoid a race
         _active_threads.append(self)
         if self.server_mode:
-            self._log(DEBUG, 'starting thread (server mode): %s' % hex(long(id(self)) & 0xffffffffL))
+            self._log(DEBUG, 'starting thread (server mode): %s' % hex(long(id(self)) & long(0xffffffff)))
         else:
-            self._log(DEBUG, 'starting thread (client mode): %s' % hex(long(id(self)) & 0xffffffffL))
+            self._log(DEBUG, 'starting thread (client mode): %s' % hex(long(id(self)) & long(0xffffffff)))
         try:
             try:
                 self.packetizer.write_all(self.local_version + '\r\n')
diff --git a/paramiko/util.py b/paramiko/util.py
index 4ce86ed..a29f9a5 100644
--- a/paramiko/util.py
+++ b/paramiko/util.py
@@ -25,7 +25,7 @@ from __future__ import generators
 import array
 from binascii import hexlify, unhexlify
 import errno
-import sys
+
 import struct
 import traceback
 import threading
@@ -33,6 +33,9 @@ import threading
 from paramiko.common import *
 from paramiko.config import SSHConfig
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
 
 # Change by RogerB - python < 2.3 doesn't have enumerate so we implement it
 if sys.version_info < (2,3):
@@ -48,7 +51,7 @@ if sys.version_info < (2,3):
 
 def inflate_long(s, always_positive=False):
     "turns a normalized byte string into a long-int (adapted from Crypto.Util.number)"
-    out = 0L
+    out = 0
     negative = 0
     if not always_positive and (len(s) > 0) and (ord(s[0]) >= 0x80):
         negative = 1
@@ -60,7 +63,7 @@ def inflate_long(s, always_positive=False):
     for i in range(0, len(s), 4):
         out = (out << 32) + struct.unpack('>I', s[i:i+4])[0]
     if negative:
-        out -= (1L << (8 * len(s)))
+        out -= (long(1) << (8 * len(s)))
     return out
 
 def deflate_long(n, add_sign_padding=True):
@@ -69,7 +72,7 @@ def deflate_long(n, add_sign_padding=True):
     s = ''
     n = long(n)
     while (n != 0) and (n != -1):
-        s = struct.pack('>I', n & 0xffffffffL) + s
+        s = struct.pack('>I', n & long(0xffffffff)) + s
         n = n >> 32
     # strip off leading zeros, FFs
     for i in enumerate(s):
@@ -282,7 +285,7 @@ def retry_on_signal(function):
 
 class Counter (object):
     """Stateful counter for CTR mode crypto"""
-    def __init__(self, nbits, initial_value=1L, overflow=0L):
+    def __init__(self, nbits, initial_value=long(1), overflow=0):
         self.blocksize = nbits / 8
         self.overflow = overflow
         # start with value - 1 so we don't have to store intermediate values when counting
@@ -306,6 +309,6 @@ class Counter (object):
         self.value = array.array('c', '\x00' * (self.blocksize - len(x)) + x)
         return self.value.tostring()
 
-    def new(cls, nbits, initial_value=1L, overflow=0L):
+    def new(cls, nbits, initial_value=long(1), overflow=0):
         return cls(nbits, initial_value=initial_value, overflow=overflow)
     new = classmethod(new)
diff --git a/tests/test_kex.py b/tests/test_kex.py
index f6e6996..16700d8 100644
--- a/tests/test_kex.py
+++ b/tests/test_kex.py
@@ -27,6 +27,10 @@ from paramiko.kex_group1 import KexGroup1
 from paramiko.kex_gex import KexGex
 from paramiko import Message
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 
 class FakeRng (object):
     def read(self, n):
@@ -41,7 +45,7 @@ class FakeKey (object):
 
 
 class FakeModulusPack (object):
-    P = 0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFFL
+    P = long(0xFFFFFFFFFFFFFFFFC90FDAA22168C234C4C6628B80DC1CD129024E088A67CC74020BBEA63B139B22514A08798E3404DDEF9519B3CD3A431B302B0A6DF25F14374FE1356D6D51C245E485B576625E7EC6F44C42E9A637ED6B0BFF5CB6F406B7EDEE386BFB5A899FA5AE9F24117C4B1FE649286651ECE65381FFFFFFFFFFFFFFFF)
     G = 2
     def get_modulus(self, min, ask, max):
         return self.G, self.P
@@ -75,7 +79,7 @@ class FakeTransport (object):
 
 class KexTest (unittest.TestCase):
 
-    K = 14730343317708716439807310032871972459448364195094179797249681733965528989482751523943515690110179031004049109375612685505881911274101441415545039654102474376472240501616988799699744135291070488314748284283496055223852115360852283821334858541043710301057312858051901453919067023103730011648890038847384890504L
+    K = long(14730343317708716439807310032871972459448364195094179797249681733965528989482751523943515690110179031004049109375612685505881911274101441415545039654102474376472240501616988799699744135291070488314748284283496055223852115360852283821334858541043710301057312858051901453919067023103730011648890038847384890504)
 
     def setUp(self):
         pass
@@ -204,7 +208,7 @@ class KexTest (unittest.TestCase):
         msg.add_mpint(12345)
         msg.rewind()
         kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_INIT, msg)
-        K = 67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581L
+        K = long(67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581)
         H = 'CE754197C21BF3452863B4F44D0B3951F12516EF'
         x = '210000000866616B652D6B6579000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D40000000866616B652D736967'
         self.assertEquals(K, transport._K)
@@ -231,7 +235,7 @@ class KexTest (unittest.TestCase):
         msg.add_mpint(12345)
         msg.rewind()
         kex.parse_next(paramiko.kex_gex._MSG_KEXDH_GEX_INIT, msg)
-        K = 67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581L
+        K = long(67592995013596137876033460028393339951879041140378510871612128162185209509220726296697886624612526735888348020498716482757677848959420073720160491114319163078862905400020959196386947926388406687288901564192071077389283980347784184487280885335302632305026248574716290537036069329724382811853044654824945750581)
         H = 'B41A06B2E59043CEFC1AE16EC31F1E2D12EC455B'
         x = '210000000866616B652D6B6579000000807E2DDB1743F3487D6545F04F1C8476092FB912B013626AB5BCEB764257D88BBA64243B9F348DF7B41B8C814A995E00299913503456983FFB9178D3CD79EB6D55522418A8ABF65375872E55938AB99A84A0B5FC8A1ECC66A7C3766E7E0F80B7CE2C9225FC2DD683F4764244B72963BBB383F529DCF0C5D17740B8A2ADBE9208D40000000866616B652D736967'
         self.assertEquals(K, transport._K)
diff --git a/tests/test_message.py b/tests/test_message.py
index 7bfd44d..10e6af1 100644
--- a/tests/test_message.py
+++ b/tests/test_message.py
@@ -20,6 +20,10 @@
 Some unit tests for ssh protocol message blocks.
 """
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 import unittest
 from paramiko.message import Message
 
@@ -50,10 +54,10 @@ class MessageTest (unittest.TestCase):
 
         msg = Message()
         msg.add_int64(5)
-        msg.add_int64(0xf5e4d3c2b109L)
+        msg.add_int64(long(0xf5e4d3c2b109))
         msg.add_mpint(17)
-        msg.add_mpint(0xf5e4d3c2b109L)
-        msg.add_mpint(-0x65e4d3c2b109L)
+        msg.add_mpint(long(0xf5e4d3c2b109))
+        msg.add_mpint(long(-0x65e4d3c2b109))
         self.assertEquals(str(msg), self.__c)
 
     def test_2_decode(self):
@@ -73,15 +77,15 @@ class MessageTest (unittest.TestCase):
 
         msg = Message(self.__c)
         self.assertEquals(msg.get_int64(), 5)
-        self.assertEquals(msg.get_int64(), 0xf5e4d3c2b109L)
+        self.assertEquals(msg.get_int64(), long(0xf5e4d3c2b109))
         self.assertEquals(msg.get_mpint(), 17)
-        self.assertEquals(msg.get_mpint(), 0xf5e4d3c2b109L)
-        self.assertEquals(msg.get_mpint(), -0x65e4d3c2b109L)
+        self.assertEquals(msg.get_mpint(), long(0xf5e4d3c2b109))
+        self.assertEquals(msg.get_mpint(), long(-0x65e4d3c2b109))
 
     def test_3_add(self):
         msg = Message()
         msg.add(5)
-        msg.add(0x1122334455L)
+        msg.add(long(0x1122334455))
         msg.add(True)
         msg.add('cat')
         msg.add(['a', 'b'])
@@ -90,7 +94,7 @@ class MessageTest (unittest.TestCase):
     def test_4_misc(self):
         msg = Message(self.__d)
         self.assertEquals(msg.get_int(), 5)
-        self.assertEquals(msg.get_mpint(), 0x1122334455L)
+        self.assertEquals(msg.get_mpint(), long(0x1122334455))
         self.assertEquals(msg.get_so_far(), self.__d[:13])
         self.assertEquals(msg.get_remainder(), self.__d[13:])
         msg.rewind()
diff --git a/tests/test_transport.py b/tests/test_transport.py
index d3d1c98..171ff3a 100644
--- a/tests/test_transport.py
+++ b/tests/test_transport.py
@@ -29,6 +29,10 @@ import threading
 import unittest
 import random
 
+import six
+if six.PY3:
+    long = lambda x: int(x)
+
 from paramiko import Transport, SecurityOptions, ServerInterface, RSAKey, DSSKey, \
     SSHException, BadAuthenticationType, InteractiveQuery, ChannelException
 from paramiko import AUTH_FAILED, AUTH_PARTIALLY_SUCCESSFUL, AUTH_SUCCESSFUL
@@ -158,7 +162,7 @@ class TransportTest(ParamikoTest):
             pass
             
     def test_2_compute_key(self):
-        self.tc.K = 123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929L
+        self.tc.K = long(123281095979686581523377256114209720774539068973101330872763622971399429481072519713536292772709507296759612401802191955568143056534122385270077606457721553469730659233569339356140085284052436697480759510519672848743794433460113118986816826624865291116513647975790797391795651716378444844877749505443714557929)
         self.tc.H = unhexlify('0C8307CDE6856FF30BA93684EB0F04C2520E9ED3')
         self.tc.session_id = self.tc.H
         key = self.tc._compute_key('C', 32)