diff --git a/NEWS b/NEWS
index 6b13484c..8e83bf59 100644
--- a/NEWS
+++ b/NEWS
@@ -1,3 +1,121 @@
+0MQ version 4.1.0, released on 2014/xx/xx
+=========================================
+
+
+0MQ version 4.0.0 (RC1), released on 2013/09/20
+===============================================
+
+Major changes
+-------------
+
+* New wire level protocol, ZMTP/3.0, see http://rfc.zeromq.org/spec:23.
+  Does not yet implement the SUBSCRIBE, CANCEL, PING, and PONG commands.
+  
+* New security framework, from plain user+password to strong encryption, 
+  see section below. See http://hintjens.com/blog:49 for a tutorial.
+  
+* New ZMQ_STREAM socket type for working as a TCP client or server. See: 
+  tests/test_stream.cpp.
+  
+Improvements
+------------
+
+* You can now connect to an inproc:// endpoint that does not already
+  exist. This means inproc:// no longer needs careful set-up, but it may
+  break code that relied on the old behaviour. See: 
+  tests/test_inproc_connect.cpp.
+ 
+* Libzmq now checks socket types at connection time, so that trying to 
+  connect a 'wrong' socket type will fail.
+  
+* New zmq_ctx_shutdown API method will shutdown a context and send ETERM
+  to blocking calls, without blocking. Use zmq_ctx_term to finalise the
+  process.
+  
+* The regression test suite has been significantly extended and improved.
+  
+* Contexts can now be terminated in forked child processes. See: 
+  tests/test_fork.cpp.
+  
+* zmq_disconnect now respects the linger setting on sockets.
+
+* New zmq_send_const API method to send constant data (without copying).
+  See: tests/test_inproc_connect.cpp.
+  
+* Added CMake support for static libraries.
+
+* Added test cases for socket semantics as defined in RFCs 28, 29, 30, 31.
+  See: tests/test_spec_*.cpp.
+
+* New socket option, ZMQ_PROBE_ROUTER triggers an empty message on connect.
+  See: tests/test_probe_router.cpp.
+  
+* New socket option, ZMQ_REQ_CORRELATE allows for correlation of replies 
+  from a REP socket. See: tests/test_req_correlate.cpp.
+  
+* New socket option, ZMQ_REQ_RELAXED, lets you disable the state machine 
+  on a REQ socket, so you can send multiple requests without waiting for 
+  replies, and without getting an EFSM error. See: 
+  tests/test_req_relaxed.cpp.
+  
+* New socket option, ZMQ_CONFLATE restricts the outgoing and incoming 
+  socket buffers to a single message. See: tests/test_conflate.cpp.
+
+Deprecated Options
+------------------
+
+* ZMQ_IPV4ONLY deprecated and renamed to ZMQ_IPV6 so that options are
+  consistently "off" by default. 
+
+* ZMQ_DELAY_ATTACH_ON_CONNECT deprecated, and renamed to ZMQ_IMMEDIATE.
+  See: tests/test_immediate.cpp.
+
+Security Framework
+------------------
+
+Based on new ZMTP wire level protocol that negotiates a security 
+"mechanism" between client and server before exchanging any other data.
+
+Security mechanisms are extensible. ZMTP defines three by default:
+
+* NULL - classic ZeroMQ, with no authentication. See 
+  http://rfc.zeromq.org/spec:23.
+  
+* PLAIN - plain-text username + password authentication. See
+  http://rfc.zeromq.org/spec:24.
+
+* CURVE - secure authentication and encryption based on elliptic curve 
+  cryptography, using the Curve25519 algorithm from Daniel Bernstein and 
+  based on CurveCP's security handshake. See http://rfc.zeromq.org/spec:25, 
+  http://rfc.zeromq.org/spec:26, and http://curvecp.org.
+  
+Authentication is done by pluggable "authenticators" that connect to libzmq
+over an inproc endpoint, see http://rfc.zeromq.org/spec:27.
+
+Socket options to configure PLAIN security on client or server:
+
+* ZMQ_PLAIN_SERVER, ZMQ_PLAIN_USERNAME, ZMQ_PLAIN_PASSWORD. See 
+  tests/test_security_plain.
+  
+Socket options to configure CURVE security on client or server:
+
+* ZMQ_CURVE_SERVER, ZMQ_CURVE_PUBLICKEY, ZMQ_CURVE_SECRETKEY, 
+  ZMQ_CURVE_SERVERKEY. See tests/test_security_curve.cpp.
+  
+Socket options to configure "domain" for ZAP handler:
+ 
+* ZMQ_ZAP_DOMAIN, see tests/test_security_null.cpp.
+
+Support for encoding/decoding CURVE binary keys to ASCII:
+
+* zmq_z85_encode, zmq_z85_decode.
+
+Other issues addressed in this release
+--------------------------------------
+
+* LIBZMQ-525 Multipart upstreaming from XSUB to XPUB
+
+
 0MQ version 3.2.4 stable, released on 2013/09/20
 ================================================
 
diff --git a/include/zmq.h b/include/zmq.h
index 0aeafeb0..a6aa252f 100644
--- a/include/zmq.h
+++ b/include/zmq.h
@@ -72,8 +72,8 @@ typedef unsigned __int16 uint16_t;
 /******************************************************************************/
 
 /*  Version macros for compile-time API version detection                     */
-#define ZMQ_VERSION_MAJOR 3
-#define ZMQ_VERSION_MINOR 3
+#define ZMQ_VERSION_MAJOR 4
+#define ZMQ_VERSION_MINOR 1
 #define ZMQ_VERSION_PATCH 0
 
 #define ZMQ_MAKE_VERSION(major, minor, patch) \
diff --git a/src/Makefile.am b/src/Makefile.am
index 0f508644..0e66c395 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -88,7 +88,7 @@ libzmq_la_SOURCES = \
     dealer.hpp \
     xsub.hpp \
     ypipe.hpp \
-    ypipe_flat.hpp \
+    ypipe_base.hpp \
     yqueue.hpp \
     address.cpp \
     clock.cpp \
diff --git a/tools/Makefile.am b/tools/Makefile.am
index 7f8d6a93..955acbd9 100644
--- a/tools/Makefile.am
+++ b/tools/Makefile.am
@@ -1,4 +1,4 @@
-EXTRA_DIST = curve_keygen.c z85_codec.h
+EXTRA_DIST = curve_keygen.c 
 
 INCLUDES = -I$(top_srcdir)/include