diff --git a/configure.ac b/configure.ac
index eb81a7eb71..fa54431fc1 100644
--- a/configure.ac
+++ b/configure.ac
@@ -12,7 +12,7 @@ AC_PREREQ(2.59)
 # In the SVN trunk, the version should always be the next anticipated release
 # version with the "-pre" suffix.  (We used to use "-SNAPSHOT" but this pushed
 # the size of one file name in the dist tarfile over the 99-char limit.)
-AC_INIT([Protocol Buffers],[2.2.1-pre],[protobuf@googlegroups.com],[protobuf])
+AC_INIT([Protocol Buffers],[2.3.0-pre],[protobuf@googlegroups.com],[protobuf])
 
 
 AC_CONFIG_SRCDIR(src/google/protobuf/message.cc)
diff --git a/java/pom.xml b/java/pom.xml
index 307bc0b785..dd28a46dae 100644
--- a/java/pom.xml
+++ b/java/pom.xml
@@ -10,7 +10,7 @@
   </parent>
   <groupId>com.google.protobuf</groupId>
   <artifactId>protobuf-java</artifactId>
-  <version>2.2.1-pre</version>
+  <version>2.3.0-pre</version>
   <packaging>jar</packaging>
   <name>Protocol Buffer Java API</name>
   <description>
diff --git a/python/setup.py b/python/setup.py
index 4051c53389..a547261670 100755
--- a/python/setup.py
+++ b/python/setup.py
@@ -98,7 +98,7 @@ if __name__ == '__main__':
     generate_proto("../src/google/protobuf/descriptor.proto")
 
   setup(name = 'protobuf',
-        version = '2.2.1-pre',
+        version = '2.3.0-pre',
         packages = [ 'google' ],
         namespace_packages = [ 'google' ],
         test_suite = 'setup.MakeTestSuite',
diff --git a/src/Makefile.am b/src/Makefile.am
index 1fcbf620f4..6734a5d1c6 100644
--- a/src/Makefile.am
+++ b/src/Makefile.am
@@ -76,7 +76,7 @@ nobase_include_HEADERS =                                       \
 lib_LTLIBRARIES = libprotobuf-lite.la libprotobuf.la libprotoc.la
 
 libprotobuf_lite_la_LIBADD = $(PTHREAD_LIBS)
-libprotobuf_lite_la_LDFLAGS = -version-info 5:0:0
+libprotobuf_lite_la_LDFLAGS = -version-info 6:0:0
 libprotobuf_lite_la_SOURCES =                                  \
   google/protobuf/stubs/common.cc                              \
   google/protobuf/stubs/once.cc                                \
@@ -95,7 +95,7 @@ libprotobuf_lite_la_SOURCES =                                  \
   google/protobuf/io/zero_copy_stream_impl_lite.cc
 
 libprotobuf_la_LIBADD = $(PTHREAD_LIBS)
-libprotobuf_la_LDFLAGS = -version-info 5:0:0
+libprotobuf_la_LDFLAGS = -version-info 6:0:0
 libprotobuf_la_SOURCES =                                       \
   $(libprotobuf_lite_la_SOURCES)                               \
   google/protobuf/stubs/strutil.cc                             \
@@ -123,7 +123,7 @@ libprotobuf_la_SOURCES =                                       \
   google/protobuf/compiler/parser.cc
 
 libprotoc_la_LIBADD = $(PTHREAD_LIBS) libprotobuf.la
-libprotoc_la_LDFLAGS = -version-info 5:0:0
+libprotoc_la_LDFLAGS = -version-info 6:0:0
 libprotoc_la_SOURCES =                                         \
   google/protobuf/compiler/code_generator.cc                   \
   google/protobuf/compiler/command_line_interface.cc           \
diff --git a/src/google/protobuf/descriptor.pb.h b/src/google/protobuf/descriptor.pb.h
index 7df3ae1609..2743b6f5f9 100644
--- a/src/google/protobuf/descriptor.pb.h
+++ b/src/google/protobuf/descriptor.pb.h
@@ -8,12 +8,12 @@
 
 #include <google/protobuf/stubs/common.h>
 
-#if GOOGLE_PROTOBUF_VERSION < 2002000
+#if GOOGLE_PROTOBUF_VERSION < 2003000
 #error This file was generated by a newer version of protoc which is
 #error incompatible with your Protocol Buffer headers.  Please update
 #error your headers.
 #endif
-#if 2002001 < GOOGLE_PROTOBUF_MIN_PROTOC_VERSION
+#if 2003000 < GOOGLE_PROTOBUF_MIN_PROTOC_VERSION
 #error This file was generated by an older version of protoc which is
 #error incompatible with your Protocol Buffer headers.  Please
 #error regenerate this file with a newer version of protoc.
diff --git a/src/google/protobuf/stubs/common.h b/src/google/protobuf/stubs/common.h
index 848ec3ab52..551ee4aac6 100644
--- a/src/google/protobuf/stubs/common.h
+++ b/src/google/protobuf/stubs/common.h
@@ -83,24 +83,24 @@ namespace internal {
 
 // The current version, represented as a single integer to make comparison
 // easier:  major * 10^6 + minor * 10^3 + micro
-#define GOOGLE_PROTOBUF_VERSION 2002001
+#define GOOGLE_PROTOBUF_VERSION 2003000
 
 // The minimum library version which works with the current version of the
 // headers.
-#define GOOGLE_PROTOBUF_MIN_LIBRARY_VERSION 2002000
+#define GOOGLE_PROTOBUF_MIN_LIBRARY_VERSION 2003000
 
 // The minimum header version which works with the current version of
 // the library.  This constant should only be used by protoc's C++ code
 // generator.
-static const int kMinHeaderVersionForLibrary = 2002000;
+static const int kMinHeaderVersionForLibrary = 2003000;
 
 // The minimum protoc version which works with the current version of the
 // headers.
-#define GOOGLE_PROTOBUF_MIN_PROTOC_VERSION 2002000
+#define GOOGLE_PROTOBUF_MIN_PROTOC_VERSION 2003000
 
 // The minimum header version which works with the current version of
 // protoc.  This constant should only be used in VerifyVersion().
-static const int kMinHeaderVersionForProtoc = 2002000;
+static const int kMinHeaderVersionForProtoc = 2003000;
 
 // Verifies that the headers and libraries are compatible.  Use the macro
 // below to call this.