The do_handshake() method of SSL objects now adjusts the blocking mode of
the SSL structure if necessary (as other methods already do).
diff --git a/Misc/NEWS b/Misc/NEWS
index e9b3caf..b9bdc97 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -25,6 +25,9 @@
 Library
 -------
 
+- The do_handshake() method of SSL objects now adjusts the blocking mode of
+  the SSL structure if necessary (as other methods already do).
+
 - Issue #7507: Quote "!" in pipes.quote(); it is special to some shells.
 
 - Issue #5238: Calling makefile() on an SSL object would prevent the
diff --git a/Modules/_ssl.c b/Modules/_ssl.c
index d19bf2d..e81c219 100644
--- a/Modules/_ssl.c
+++ b/Modules/_ssl.c
@@ -455,7 +455,12 @@
 {
 	int ret;
 	int err;
-	int sockstate;
+	int sockstate, nonblocking;
+
+	/* just in case the blocking state of the socket has been changed */
+	nonblocking = (self->Socket->sock_timeout >= 0.0);
+	BIO_set_nbio(SSL_get_rbio(self->ssl), nonblocking);
+	BIO_set_nbio(SSL_get_wbio(self->ssl), nonblocking);
 
 	/* Actually negotiate SSL connection */
 	/* XXX If SSL_do_handshake() returns 0, it's also a failure. */