diff -r c8f283cd3e6e Lib/imaplib.py
--- a/Lib/imaplib.py	Wed Apr 27 19:30:16 2011 +0200
+++ b/Lib/imaplib.py	Wed Apr 27 16:40:55 2011 -0400
@@ -1177,25 +1177,30 @@
 
         """IMAP4 client class over SSL connection
 
-        Instantiate with: IMAP4_SSL([host[, port[, keyfile[, certfile]]]])
+        Instantiate with: IMAP4_SSL([host[, port[, keyfile[, certfile[, ssl_context]]]]])
 
                 host - host's name (default: localhost);
-                port - port number (default: standard IMAP4 SSL port).
+                port - port number (default: standard IMAP4 SSL port);
                 keyfile - PEM formatted file that contains your private key (default: None);
                 certfile - PEM formatted certificate chain file (default: None);
-
+                ssl_context - a SSLContext object that contains your certificate chain and private key,
+                if ssl_context is provided, the parameters keyfile and certfile are ignored (default: None);
         for more documentation see the docstring of the parent class IMAP4.
         """
 
 
-        def __init__(self, host = '', port = IMAP4_SSL_PORT, keyfile = None, certfile = None):
+        def __init__(self, host = '', port = IMAP4_SSL_PORT, keyfile = None, certfile = None, ssl_context = None):
             self.keyfile = keyfile
             self.certfile = certfile
+            self.ssl_context = ssl_context
             IMAP4.__init__(self, host, port)
 
         def _create_socket(self):
             sock = IMAP4._create_socket(self)
-            return ssl.wrap_socket(sock, self.keyfile, self.certfile)
+            if self.ssl_context:
+                return self.ssl_context.wrap_socket(sock)
+            else:
+                return ssl.wrap_socket(sock, self.keyfile, self.certfile)
 
         def open(self, host='', port=IMAP4_SSL_PORT):
             """Setup connection to remote server on "host:port".
diff -r c8f283cd3e6e Lib/test/test_imaplib.py
--- a/Lib/test/test_imaplib.py	Wed Apr 27 19:30:16 2011 +0200
+++ b/Lib/test/test_imaplib.py	Wed Apr 27 16:40:55 2011 -0400
@@ -258,11 +258,26 @@
     port = 993
     imap_class = IMAP4_SSL
 
+    def check_logincapa(self, server):
+        for cap in server.capabilities:
+            self.assertIsInstance(cap, str)
+        self.assertFalse('LOGINDISABLED' in server.capabilities)
+        self.assertTrue('AUTH=PLAIN' in server.capabilities)
+        
     def test_logincapa(self):
-        for cap in self.server.capabilities:
-            self.assertIsInstance(cap, str)
-        self.assertFalse('LOGINDISABLED' in self.server.capabilities)
-        self.assertTrue('AUTH=PLAIN' in self.server.capabilities)
+       self.check_logincapa(self.server)
+       
+    def test_logincapa_with_client_private_key_file(self):
+        with transient_internet(self.host):
+            _server = self.imap_class(self.host, self.port, certfile = CERTFILE)
+            self.check_logincapa(_server)
+            
+    def test_logincapa_with_client_ssl_context(self):
+        with transient_internet(self.host):
+            ssl_context = ssl.SSLContext(ssl.PROTOCOL_SSLv23)
+            ssl_context.load_cert_chain(CERTFILE)
+            _server = self.imap_class(self.host, self.port, ssl_context = ssl_context)
+            self.check_logincapa(_server)
 
 
 def test_main():