Hello, I'm just starting to use twisted (having quickly read through the book "Twisted: Network Programming Essentials"), and I am unable to successfully use one of the example scripts: doc/conch/examples/ sshsimpleserver.py . I am using python 2.5.2 and today's svn of twisted and pycrypto on RedHat AS5 x84-64. I experienced similar results with 8.1.0 . I am able to start the server with no problem, but when I start a client that connects to it, I get: 2008-09-23 21:51:08+0000 [-] Log opened. 2008-09-23 21:51:08+0000 [-] __main__.ExampleFactory starting on 5022 2008-09-23 21:51:08+0000 [-] Starting factory <__main__.ExampleFactory instance at 0x17e60a28> 2008-09-23 21:51:10+0000 [__main__.ExampleFactory] disabling diffie- hellman-group-exchange because we cannot find moduli file 2008-09-23 21:51:10+0000 [SSHServerTransport,0,127.0.0.1] kex alg, key alg: diffie-hellman-group1-sha1 ssh-rsa 2008-09-23 21:51:10+0000 [SSHServerTransport,0,127.0.0.1] outgoing: aes256-ctr hmac-sha1 none 2008-09-23 21:51:10+0000 [SSHServerTransport,0,127.0.0.1] incoming: aes256-ctr hmac-sha1 none 2008-09-23 21:51:10+0000 [SSHServerTransport,0,127.0.0.1] Unhandled Error Traceback (most recent call last): File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/python/log.py", line 51, in callWithLogger return callWithContext({"system": lp}, func, *args, **kw) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/python/log.py", line 36, in callWithContext return context.call({ILogContext: newCtx}, func, *args, **kw) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/python/context.py", line 59, in callWithContext return self.currentContext().callWithContext(ctx, func, *args, **kw) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/python/context.py", line 37, in callWithContext return func(*args,**kw) --- <exception caught here> --- File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/internet/selectreactor.py", line 146, in _doReadOrWrite why = getattr(selectable, method)() File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/internet/tcp.py", line 463, in doRead return self.protocol.dataReceived(data) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/conch/ssh/transport.py", line 314, in dataReceived self.dispatchMessage(messageNum, packet[1:]) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/conch/ssh/transport.py", line 329, in dispatchMessage f(payload) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/conch/ssh/transport.py", line 740, in ssh_KEX_DH_GEX_REQUEST_OLD NS(self.factory.privateKeys[self.keyAlg].sign(exchangeHash))) File "/usr/DiamondBack/stow/twisted-20080923_svn-py2.5/lib/ python2.5/site-packages/twisted/conch/ssh/keys.py", line 659, in sign signature = self.keyObject.sign(digest, '')[0] File "/usr/DiamondBack/stow/pycrypto-20080923_git-py2.5/lib/ python2.5/site-packages/Crypto/PublicKey/pubkey.py", line 76, in sign return self._sign(M, K) exceptions.TypeError: _sign() takes exactly 2 arguments (3 given) 2008-09-23 21:51:10+0000 [SSHServerTransport,0,127.0.0.1] connection lost I have tried starting the client both as 'ssh localhost -p 5022' as well as running the sshsimpleclient.py script with the same results. I have also tried connecting from a different host into the server, with the same results. Any help in resolving this issue and realizing a working example of an ssh server would be greatly appreciated. Thank you, Glen Mabey