diff -up xserver/configure.ac.vnc xserver/configure.ac
--- xserver/configure.ac.vnc	2013-04-09 16:35:38.000000000 +0200
+++ xserver/configure.ac	2013-04-09 18:16:31.000000000 +0200
@@ -72,6 +72,7 @@ dnl forcing an entire recompile.x
 AC_CONFIG_HEADERS(include/version-config.h)
 
 AM_PROG_AS
+AC_PROG_CXX
 AC_PROG_LN_S
 AC_LIBTOOL_WIN32_DLL
 AC_DISABLE_STATIC
@@ -1573,6 +1574,10 @@ if test "x$XVFB" = xyes; then
 	AC_SUBST([XVFB_SYS_LIBS])
 fi
 
+dnl Xvnc DDX
+AC_SUBST([XVNC_CPPFLAGS], ["-DHAVE_DIX_CONFIG_H $XSERVER_CFLAGS"])
+AC_SUBST([XVNC_LIBS], ["$FB_LIB $FIXES_LIB $XEXT_LIB $CONFIG_LIB $DBE_LIB $RECORD_LIB $GLX_LIBS $RANDR_LIB $RENDER_LIB $DAMAGE_LIB $MIEXT_SYNC_LIB $MIEXT_DAMAGE_LIB $MIEXT_SHADOW_LIB $XI_LIB $XKB_LIB $XKB_STUB_LIB $COMPOSITE_LIB $MAIN_LIB"])
+AC_SUBST([XVNC_SYS_LIBS], ["$GLX_SYS_LIBS"])
 
 dnl Xnest DDX
 
@@ -1608,6 +1613,8 @@ if test "x$XORG" = xauto; then
 fi
 AC_MSG_RESULT([$XORG])
 
+AC_DEFINE_UNQUOTED(XORG_VERSION_CURRENT, [$VENDOR_RELEASE], [Current Xorg version])
+
 if test "x$XORG" = xyes; then
 	XORG_DDXINCS='-I$(top_srcdir)/hw/xfree86 -I$(top_srcdir)/hw/xfree86/include -I$(top_srcdir)/hw/xfree86/common'
 	XORG_OSINCS='-I$(top_srcdir)/hw/xfree86/os-support -I$(top_srcdir)/hw/xfree86/os-support/bus -I$(top_srcdir)/os'
@@ -1827,7 +1834,6 @@ if test "x$XORG" = xyes; then
 	AC_DEFINE(XORG_SERVER, 1, [Building Xorg server])
 	AC_DEFINE(XORGSERVER, 1, [Building Xorg server])
 	AC_DEFINE(XFree86Server, 1, [Building XFree86 server])
-	AC_DEFINE_UNQUOTED(XORG_VERSION_CURRENT, [$VENDOR_RELEASE], [Current Xorg version])
 	AC_DEFINE(NEED_XF86_TYPES, 1, [Need XFree86 typedefs])
 	AC_DEFINE(NEED_XF86_PROTOTYPES, 1, [Need XFree86 helper functions])
 	AC_DEFINE(__XSERVERNAME__, "Xorg", [Name of X server])
@@ -2292,6 +2298,7 @@ hw/dmx/Makefile
 hw/dmx/man/Makefile
 hw/vfb/Makefile
 hw/vfb/man/Makefile
+hw/vnc/Makefile
 hw/xnest/Makefile
 hw/xnest/man/Makefile
 hw/xwin/Makefile
diff -up xserver/hw/Makefile.am.vnc xserver/hw/Makefile.am
--- xserver/hw/Makefile.am.vnc	2013-04-09 16:36:46.000000000 +0200
+++ xserver/hw/Makefile.am	2013-04-09 18:16:31.000000000 +0200
@@ -33,7 +33,8 @@ SUBDIRS =			\
 	$(XNEST_SUBDIRS)	\
 	$(DMX_SUBDIRS)		\
 	$(KDRIVE_SUBDIRS)	\
-	$(XQUARTZ_SUBDIRS)
+	$(XQUARTZ_SUBDIRS)	\
+	vnc
 
 DIST_SUBDIRS = dmx xfree86 vfb xnest xwin xquartz kdrive
 
diff -up xserver/mi/miinitext.c.vnc xserver/mi/miinitext.c
--- xserver/mi/miinitext.c.vnc	2013-04-09 16:37:21.000000000 +0200
+++ xserver/mi/miinitext.c	2013-04-09 18:16:31.000000000 +0200
@@ -112,6 +112,10 @@ SOFTWARE.
 #include "micmap.h"
 #include "globals.h"
 
+#ifdef TIGERVNC
+extern void vncExtensionInit(INITARGS);
+#endif
+
 /* The following is only a small first step towards run-time
  * configurable extensions.
  */
@@ -238,6 +242,9 @@ EnableDisableExtensionError(const char *
 
 /* List of built-in (statically linked) extensions */
 static ExtensionModule staticExtensions[] = {
+#ifdef TIGERVNC
+    {vncExtensionInit, "VNC-EXTENSION", NULL},
+#endif
     {GEExtensionInit, "Generic Event Extension", &noGEExtension},
     {ShapeExtensionInit, "SHAPE", NULL},
 #ifdef MITSHM
diff -up xserver/os/WaitFor.c.vnc xserver/os/WaitFor.c
--- xserver/os/WaitFor.c.vnc	2013-04-10 14:51:13.000000000 +0200
+++ xserver/os/WaitFor.c	2013-04-10 14:55:40.000000000 +0200
@@ -124,6 +124,9 @@ static void DoTimer(OsTimerPtr timer, CA
 static void CheckAllTimers(void);
 static OsTimerPtr timers = NULL;
 
+extern void vncWriteBlockHandler(fd_set *fds);
+extern void vncWriteWakeupHandler(int nfds, fd_set *fds);
+
 /*****************
  * WaitForSomething:
  *     Make the server suspend until there is
@@ -149,6 +152,7 @@ WaitForSomething(int *pClientsReady)
     INT32 timeout = 0;
     fd_set clientsReadable;
     fd_set clientsWritable;
+    fd_set socketsWritable;
     int curclient;
     int selecterr;
     static int nready;
@@ -207,6 +211,9 @@ WaitForSomething(int *pClientsReady)
             XFD_COPYSET(&AllSockets, &LastSelectMask);
         }
 
+        FD_ZERO(&socketsWritable);
+        vncWriteBlockHandler(&socketsWritable);
+
         BlockHandler((pointer) &wt, (pointer) &LastSelectMask);
         if (NewOutputPending)
             FlushAllOutput();
@@ -218,10 +225,20 @@ WaitForSomething(int *pClientsReady)
             i = Select(MaxClients, &LastSelectMask, &clientsWritable, NULL, wt);
         }
         else {
-            i = Select(MaxClients, &LastSelectMask, NULL, NULL, wt);
+            if (AnyClientsWriteBlocked)
+            XFD_ORSET(&socketsWritable, &ClientsWriteBlocked, &socketsWritable);
+
+            if (XFD_ANYSET(&socketsWritable)) {
+                i = Select (MaxClients, &LastSelectMask, &socketsWritable, NULL, wt);
+                if (AnyClientsWriteBlocked)
+                    XFD_ANDSET(&clientsWritable, &socketsWritable, &ClientsWriteBlocked);
+            } else {
+                i = Select (MaxClients, &LastSelectMask, NULL, NULL, wt);
+            }
         }
         selecterr = GetErrno();
         WakeupHandler(i, (pointer) &LastSelectMask);
+        vncWriteWakeupHandler(i, &socketsWritable);
         if (i <= 0) {           /* An error or timeout occurred */
             if (dispatchException)
                 return 0;