diff --git a/tests/test_transport.py b/tests/test_transport.py
index c97fb16..5fcc786 100644
--- a/tests/test_transport.py
+++ b/tests/test_transport.py
@@ -540,3 +540,34 @@ class TransportTest (unittest.TestCase):
         self.assertNotEquals(self.tc.H, self.tc.session_id)
 
         schan.close()
+
+    def test_G_compression(self):
+        """
+        verify that zlib compression is basically working.
+        """
+        host_key = RSAKey.from_private_key_file('tests/test_rsa.key')
+        public_host_key = RSAKey(data=str(host_key))
+        self.ts.add_server_key(host_key)
+        self.ts.get_security_options().compression = ('zlib',)
+        self.tc.get_security_options().compression = ('zlib',)
+        event = threading.Event()
+        server = NullServer()
+        self.ts.start_server(event, server)
+        self.tc.connect(hostkey=public_host_key,
+                        username='slowdive', password='pygmalion')
+        event.wait(1.0)
+        self.assert_(event.isSet())
+        self.assert_(self.ts.is_active())
+
+        chan = self.tc.open_session()
+        self.assert_(chan.exec_command('yes'))
+        schan = self.ts.accept(1.0)
+
+        bytes = self.tc.packetizer._Packetizer__sent_bytes
+        chan.send('x' * 1024)
+        bytes2 = self.tc.packetizer._Packetizer__sent_bytes
+        # tests show this is actually compressed to *52 bytes*!  including packet overhead!  nice!! :)
+        self.assert_(bytes2 - bytes < 1024)
+
+        chan.close()
+        schan.close()