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When I compile and link against a local build of OpenSSL 1.0.0 (vanilla), I get the following errors in test_ssl:
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ERROR: testProtocolSSL2 (test.test_ssl.ThreadedTests)
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Traceback (most recent call last):
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 869, in testProtocolSSL2
 tryProtocolCombo(ssl.PROTOCOL_SSLv2, ssl.PROTOCOL_SSLv23, True)
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 736, in tryProtocolCombo
 CERTFILE, CERTFILE, client_protocol, chatty=False)
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 688, in serverParamsTest
 raise test_support.TestFailed("Unexpected exception: " + str(x))
TestFailed: Unexpected exception: [Errno 104] Connection reset by peer
======================================================================
ERROR: testProtocolSSL3 (test.test_ssl.ThreadedTests)
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Traceback (most recent call last):
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 903, in testProtocolSSL3
 tryProtocolCombo(ssl.PROTOCOL_SSLv3, ssl.PROTOCOL_SSLv23, False)
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 745, in tryProtocolCombo
 ssl.get_protocol_name(server_protocol)))
TestFailed: Client protocol SSLv23 succeeded with server protocol SSLv3!
======================================================================
ERROR: testProtocolTLS1 (test.test_ssl.ThreadedTests)
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Traceback (most recent call last):
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 914, in testProtocolTLS1
 tryProtocolCombo(ssl.PROTOCOL_TLSv1, ssl.PROTOCOL_SSLv23, False)
 File "/home/antoine/cpython/newssl/Lib/test/test_ssl.py", line 745, in tryProtocolCombo
 ssl.get_protocol_name(server_protocol)))
TestFailed: Client protocol SSLv23 succeeded with server protocol TLSv1!

Extract of SSL_CTX_new manual page:
SSLv23_method(void), SSLv23_server_method(void), SSLv23_client_method(void)
 A TLS/SSL connection established with these methods will understand
 the SSLv2, SSLv3, and TLSv1 protocol. A client will send out SSLv2
 client hello messages and will indicate that it also understands
 SSLv3 and TLSv1. A server will understand SSLv2, SSLv3, and TLSv1
 client hello messages. This is the best choice when compatibility
 is a concern.
I don't think that "Client protocol SSLv23 succeeded with server protocol SSLv3" or "Client protocol SSLv23 succeeded with server protocol TLSv1" are errors.

It begs the question of why the tests succeed with previous OpenSSL versions.
The only possibly relevant entry I could find in the OpenSSL changelog (but I'm not an expert) is the following:
 *) If no SSLv2 ciphers are used don't use an SSLv2 compatible client hello:
 this allows the use of compression and extensions. Change default cipher
 string to remove SSLv2 ciphersuites. This effectively avoids ancient SSLv2
 by default unless an application cipher string requests it.
 [Steve Henson]

All errors concern SSLv23 at server side, and another protocol at client side (SSLv23 for client and server works as expected).

After some investigation, the error does occur because of the aforementioned changelog entry (SSLv2 weak ciphers are now disabled by default). To check it I just added the following line to newPySSLObject():
 SSL_CTX_set_cipher_list(self->ctx, "ALL");
Of course this isn't desirable: we shouldn't blindly enable weak ciphers. Instead we could simply add an argument to configure allowed ciphers, and use "ALL" in our tests. Or we could add a separate method to configure ciphers.
(this begs the question of whether this is suitable post-beta1)
What do you think?

Antoine Pitrou wrote:
>
> Antoine Pitrou<pitrou@free.fr> added the comment:
>
> After some investigation, the error does occur because of the aforementioned changelog entry (SSLv2 weak ciphers are now disabled by default). To check it I just added the following line to newPySSLObject():
>
> SSL_CTX_set_cipher_list(self->ctx, "ALL");
>
> Of course this isn't desirable: we shouldn't blindly enable weak ciphers. Instead we could simply add an argument to configure allowed ciphers, and use "ALL" in our tests. Or we could add a separate method to configure ciphers.
>
> (this begs the question of whether this is suitable post-beta1)
>
> What do you think?
List of ciphers is application dependent and configure script can't 
limit users(applications) .
Roumen

> List of ciphers is application dependent and configure script can't 
> limit users(applications) .
I was obviously talking about a runtime argument to ssl.wrap_socket().

A set_ciphers() method turns out to be highly impractical, since the underlying SSL objects are created lazily when we actually connect the socket.
Therefore, I have instead opted for a new "ciphers" argument to the SSL constructor(s). Patch attached.

New patch updating docs.

Committed in r80151 (trunk), r80154 (py3k).