diff --git a/common/rfb/CMsgReader.cxx b/common/rfb/CMsgReader.cxx
index c1c6ad17c..1a84807a9 100644
--- a/common/rfb/CMsgReader.cxx
+++ b/common/rfb/CMsgReader.cxx
@@ -118,9 +118,6 @@ bool CMsgReader::readMsg()
     case msgTypeEndOfContinuousUpdates:
       ret = readEndOfContinuousUpdates();
       break;
-    case msgTypeExtendedMouseSupport:
-      ret = readSupportExtendedMouseButton();
-      break;
     default:
       throw Exception("Unknown message type %d", currentMsgType);
     }
@@ -205,6 +202,10 @@ bool CMsgReader::readMsg()
       handler->supportsQEMUKeyEvent();
       ret = true;
       break;
+    case pseudoEncodingExtendedMouseButtons:
+      handler->supportExtendedMouseButtons();
+      ret = true;
+      break;  
     default:
       ret = readRect(dataRect, rectEncoding);
       break;
@@ -457,12 +458,6 @@ bool CMsgReader::readEndOfContinuousUpdates()
   return true;
 }
 
-bool CMsgReader::readSupportExtendedMouseButton()
-{
-  handler->supportExtendedMouseButtons();
-  return true;
-}
-
 bool CMsgReader::readFramebufferUpdate()
 {
   if (!is->hasData(1 + 2))
diff --git a/common/rfb/CMsgReader.h b/common/rfb/CMsgReader.h
index 8000762bc..3b1c0ddbd 100644
--- a/common/rfb/CMsgReader.h
+++ b/common/rfb/CMsgReader.h
@@ -56,7 +56,6 @@ namespace rfb {
     bool readExtendedClipboard(int32_t len);
     bool readFence();
     bool readEndOfContinuousUpdates();
-    bool readSupportExtendedMouseButton();
 
     bool readFramebufferUpdate();
 
diff --git a/common/rfb/CMsgWriter.cxx b/common/rfb/CMsgWriter.cxx
index 8ba87e801..99ed49357 100644
--- a/common/rfb/CMsgWriter.cxx
+++ b/common/rfb/CMsgWriter.cxx
@@ -182,29 +182,22 @@ void CMsgWriter::writePointerEvent(const Point& pos, int buttonMask)
   if (p.x >= server->width()) p.x = server->width() - 1;
   if (p.y >= server->height()) p.y = server->height() - 1;
 
-  if (server->supportsExtendedMouseButtons)
-  {
-    writePointerEventExt(pos,buttonMask);
-    return;
+  if (server->supportsExtendedMouseButtons) {
+    startMsg(msgTypePointerEventExt);
+    os->writeU16(buttonMask);
+    os->writeU16(p.x);
+    os->writeU16(p.y);
+    endMsg();
+  }
+  else {
+    startMsg(msgTypePointerEvent);
+    os->writeU8(buttonMask);
+    os->writeU16(p.x);
+    os->writeU16(p.y);
+    endMsg();
   }
-
-  startMsg(msgTypePointerEvent);
-  os->writeU8(buttonMask);
-  os->writeU16(p.x);
-  os->writeU16(p.y);
-  endMsg();
-}
-
-void CMsgWriter::writePointerEventExt(const Point& p, int buttonMask)
-{
-  startMsg(msgTypePointerEventExt);
-  os->writeU16(buttonMask);
-  os->writeU16(p.x);
-  os->writeU16(p.y);
-  endMsg();
 }
 
-
 void CMsgWriter::writeClientCutText(const char* str)
 {
   if (strchr(str, '\r') != NULL)
diff --git a/common/rfb/CMsgWriter.h b/common/rfb/CMsgWriter.h
index 1b76c1da6..1b70a1d01 100644
--- a/common/rfb/CMsgWriter.h
+++ b/common/rfb/CMsgWriter.h
@@ -55,7 +55,6 @@ namespace rfb {
 
     void writeKeyEvent(uint32_t keysym, uint32_t keycode, bool down);
     void writePointerEvent(const Point& pos, int buttonMask);
-    void writePointerEventExt(const Point& pos, int buttonMask);
 
     void writeClientCutText(const char* str);
 
diff --git a/common/rfb/SMsgHandler.cxx b/common/rfb/SMsgHandler.cxx
index 972620707..bee4530f8 100644
--- a/common/rfb/SMsgHandler.cxx
+++ b/common/rfb/SMsgHandler.cxx
@@ -53,12 +53,13 @@ void SMsgHandler::setPixelFormat(const PixelFormat& pf)
 void SMsgHandler::setEncodings(int nEncodings, const int32_t* encodings)
 {
   bool firstFence, firstContinuousUpdates, firstLEDState,
-       firstQEMUKeyEvent;
+       firstQEMUKeyEvent, firstExtMouseButtonEvent;
 
   firstFence = !client.supportsFence();
   firstContinuousUpdates = !client.supportsContinuousUpdates();
   firstLEDState = !client.supportsLEDState();
   firstQEMUKeyEvent = !client.supportsEncoding(pseudoEncodingQEMUKeyEvent);
+  firstExtMouseButtonEvent = !client.supportsEncoding(pseudoEncodingExtendedMouseButtons);
 
   client.setEncodings(nEncodings, encodings);
 
@@ -72,7 +73,7 @@ void SMsgHandler::setEncodings(int nEncodings, const int32_t* encodings)
     supportsLEDState();
   if (client.supportsEncoding(pseudoEncodingQEMUKeyEvent) && firstQEMUKeyEvent)
     supportsQEMUKeyEvent();
-  if (client.supportsEncoding(pseudoEncodingExtendedMouseButtons))
+  if (client.supportsEncoding(pseudoEncodingExtendedMouseButtons) && firstExtMouseButtonEvent)
     supportsExtendedMouseButtons();
 }
 
diff --git a/common/rfb/SMsgReader.cxx b/common/rfb/SMsgReader.cxx
index cdb284d24..6cdb9e2be 100644
--- a/common/rfb/SMsgReader.cxx
+++ b/common/rfb/SMsgReader.cxx
@@ -100,7 +100,7 @@ bool SMsgReader::readMsg()
     ret = readPointerEvent();
     break;
   case msgTypePointerEventExt:
-    ret = readPointerEvenExt();
+    ret = readPointerEventExt();
     break;
   case msgTypeClientCutText:
     ret = readClientCutText();
@@ -284,7 +284,7 @@ bool SMsgReader::readPointerEvent()
   return true;
 }
 
-bool SMsgReader::readPointerEvenExt()
+bool SMsgReader::readPointerEventExt()
 {
   if (!is->hasData(2 + 2 + 2))
     return false;
diff --git a/common/rfb/SMsgReader.h b/common/rfb/SMsgReader.h
index 0a5b287d9..6b64e5df5 100644
--- a/common/rfb/SMsgReader.h
+++ b/common/rfb/SMsgReader.h
@@ -53,7 +53,7 @@ namespace rfb {
 
     bool readKeyEvent();
     bool readPointerEvent();
-    bool readPointerEvenExt();
+    bool readPointerEventExt();
     bool readClientCutText();
     bool readExtendedClipboard(int32_t len);
 
diff --git a/common/rfb/SMsgWriter.cxx b/common/rfb/SMsgWriter.cxx
index 39ce3699e..a25c558ab 100644
--- a/common/rfb/SMsgWriter.cxx
+++ b/common/rfb/SMsgWriter.cxx
@@ -50,6 +50,7 @@ SMsgWriter::SMsgWriter(ClientParams* client_, rdr::OutStream* os_)
     needSetDesktopName(false), needCursor(false),
     needCursorPos(false), needLEDState(false),
     needQEMUKeyEvent(false)
+    ,needExtMouseButtonEvent(false)
 {
 }
 
@@ -307,9 +308,8 @@ void SMsgWriter::writeExtendedMouseButtonSupport()
 {
   if (!client->supportsEncoding(pseudoEncodingExtendedMouseButtons))
     throw Exception("Client does not support Extended Mouse Buttons");
-
-  startMsg(msgTypeExtendedMouseSupport);
-  endMsg();
+ 
+  needExtMouseButtonEvent = true;
 }
 
 bool SMsgWriter::needFakeUpdate()
@@ -324,6 +324,8 @@ bool SMsgWriter::needFakeUpdate()
     return true;
   if (needQEMUKeyEvent)
     return true;
+  if (needExtMouseButtonEvent)
+    return true;
   if (needNoDataUpdate())
     return true;
 
@@ -372,6 +374,8 @@ void SMsgWriter::writeFramebufferUpdateStart(int nRects)
       nRects++;
     if (needQEMUKeyEvent)
       nRects++;
+    if (needExtMouseButtonEvent)
+      nRects++;
   }
 
   os->writeU16(nRects);
@@ -511,6 +515,11 @@ void SMsgWriter::writePseudoRects()
     writeQEMUKeyEventRect();
     needQEMUKeyEvent = false;
   }
+
+  if (needExtMouseButtonEvent) {
+    writeExtendedMouseButtonRect();
+    needExtMouseButtonEvent = false;
+  }
 }
 
 void SMsgWriter::writeNoDataRects()
@@ -744,3 +753,17 @@ void SMsgWriter::writeQEMUKeyEventRect()
   os->writeU16(0);
   os->writeU32(pseudoEncodingQEMUKeyEvent);
 }
+
+void SMsgWriter::writeExtendedMouseButtonRect()
+{
+  if (!client->supportsEncoding(pseudoEncodingExtendedMouseButtons))
+    throw Exception("Client does not support extended mouse button events");
+  if (++nRectsInUpdate > nRectsInHeader && nRectsInHeader)
+    throw Exception("SMsgWriter::writeExtendedMouseButtonRect: nRects out of sync");
+
+  os->writeS16(0);
+  os->writeS16(0);
+  os->writeU16(0);
+  os->writeU16(0);
+  os->writeU32(pseudoEncodingExtendedMouseButtons);
+}
diff --git a/common/rfb/SMsgWriter.h b/common/rfb/SMsgWriter.h
index 71cf2bbe4..e96257ea6 100644
--- a/common/rfb/SMsgWriter.h
+++ b/common/rfb/SMsgWriter.h
@@ -151,6 +151,7 @@ namespace rfb {
     void writeSetVMwareCursorPositionRect(int hotspotX, int hotspotY);
     void writeLEDStateRect(uint8_t state);
     void writeQEMUKeyEventRect();
+    void writeExtendedMouseButtonRect();
 
     ClientParams* client;
     rdr::OutStream* os;
@@ -163,6 +164,7 @@ namespace rfb {
     bool needCursorPos;
     bool needLEDState;
     bool needQEMUKeyEvent;
+    bool needExtMouseButtonEvent;
 
     typedef struct {
       uint16_t reason, result;
diff --git a/common/rfb/msgTypes.h b/common/rfb/msgTypes.h
index e2bc3423f..14fb6037f 100644
--- a/common/rfb/msgTypes.h
+++ b/common/rfb/msgTypes.h
@@ -28,8 +28,6 @@ namespace rfb {
 
   const int msgTypeEndOfContinuousUpdates = 150;
 
-  const int msgTypeExtendedMouseSupport = 151;
-
   const int msgTypeServerFence = 248;
 
   // client to server
diff --git a/java/com/tigervnc/rfb/CMsgReader.java b/java/com/tigervnc/rfb/CMsgReader.java
index 2289535d8..5dd9402e1 100644
--- a/java/com/tigervnc/rfb/CMsgReader.java
+++ b/java/com/tigervnc/rfb/CMsgReader.java
@@ -80,9 +80,6 @@ public void readMsg()
       case MsgTypes.msgTypeEndOfContinuousUpdates:
         readEndOfContinuousUpdates();
         break;
-      case MsgTypes.msgTypeExtendedMouseSupport:
-        readSupportExtendedMouseButton();
-        break;
       default:
         vlog.error("unknown message type "+type);
         throw new Exception("unknown message type");
@@ -119,6 +116,9 @@ public void readMsg()
       case Encodings.pseudoEncodingExtendedDesktopSize:
         readExtendedDesktopSize(x, y, w, h);
         break;
+      case Encodings.pseudoEncodingExtendedMouseButtons:
+        handler.SupportExtendedMouseButton();
+        break;
       case Encodings.pseudoEncodingClientRedirect:
         nUpdateRectsLeft = 0;
         readClientRedirect(x, y, w, h);
@@ -195,11 +195,6 @@ protected void readEndOfContinuousUpdates()
     handler.endOfContinuousUpdates();
   }
 
-  protected void readSupportExtendedMouseButton()
-  {
-    handler.SupportExtendedMouseButton();
-  }
-
   protected void readFramebufferUpdate()
   {
     is.skip(1);
diff --git a/java/com/tigervnc/rfb/CMsgWriter.java b/java/com/tigervnc/rfb/CMsgWriter.java
index 27a24ee2c..b92c181ea 100644
--- a/java/com/tigervnc/rfb/CMsgWriter.java
+++ b/java/com/tigervnc/rfb/CMsgWriter.java
@@ -150,26 +150,20 @@ synchronized public void writePointerEvent(Point pos, int buttonMask)
     if (p.x >= server.width()) p.x = server.width() - 1;
     if (p.y >= server.height()) p.y = server.height() - 1;
 
-    if(server.supportsExtendedMouseButtons)
-    {
-      writePointerEventExt(pos,buttonMask);
-      return;
+    if(server.supportsExtendedMouseButtons) {
+      startMsg(MsgTypes.msgTypePointerEventExt);
+      os.writeU16(buttonMask);
+      os.writeU16(p.x);
+      os.writeU16(p.y);
+      endMsg();
+    }
+    else {
+      startMsg(MsgTypes.msgTypePointerEvent);
+      os.writeU8(buttonMask);
+      os.writeU16(p.x);
+      os.writeU16(p.y);
+      endMsg();
     }
-
-    startMsg(MsgTypes.msgTypePointerEvent);
-    os.writeU8(buttonMask);
-    os.writeU16(p.x);
-    os.writeU16(p.y);
-    endMsg();
-  }
-
-  synchronized public void writePointerEventExt(Point p, int buttonMask)
-  {
-    startMsg(MsgTypes.msgTypePointerEventExt);
-    os.writeU16(buttonMask);
-    os.writeU16(p.x);
-    os.writeU16(p.y);
-    endMsg();
   }
 
   synchronized public void writeClientCutText(String str, int len)
diff --git a/java/com/tigervnc/vncviewer/Viewport.java b/java/com/tigervnc/vncviewer/Viewport.java
index 4bbf39a14..654e4dbb8 100644
--- a/java/com/tigervnc/vncviewer/Viewport.java
+++ b/java/com/tigervnc/vncviewer/Viewport.java
@@ -257,14 +257,14 @@ public int handle(MouseEvent e)
       if ((e.getModifiersEx() & MouseEvent.BUTTON3_DOWN_MASK) != 0)
         buttonMask |= 4;
       
-      //there are no masks for buttons 4 and 5 so we need to check for them only when pressed.
-      if (tk.areExtraMouseButtonsEnabled() && e.getID() == MouseEvent.MOUSE_PRESSED) {
+      //there are no masks for buttons 6 and 7 so we need to check for them only when pressed.
+      if (tk.areExtraMouseButtonsEnabled()){ 
         //Back
-        if (MouseInfo.getNumberOfButtons() >= 4 && e.getButton() == 6)
-          buttonMask |= 128;
+        if (MouseInfo.getNumberOfButtons() >= 6 && ((e.getModifiersEx() & e.getMaskForButton(6)) != 0))
+          buttonMask |= 1024;
         //Forward
-        if (MouseInfo.getNumberOfButtons() >= 5 && e.getButton() == 7)
-          buttonMask |= 256;
+        if (MouseInfo.getNumberOfButtons() >= 7 && ((e.getModifiersEx() & e.getMaskForButton(7)) != 0))
+          buttonMask |= 512;
       }
 
       if (e.getID() == MouseEvent.MOUSE_WHEEL) {
diff --git a/unix/xserver/hw/vnc/vncInput.c b/unix/xserver/hw/vnc/vncInput.c
index 0e1038658..1dbe4a3c0 100644
--- a/unix/xserver/hw/vnc/vncInput.c
+++ b/unix/xserver/hw/vnc/vncInput.c
@@ -50,7 +50,7 @@ extern const unsigned int code_map_qnum_to_xorgevdev_len;
 extern const unsigned short code_map_qnum_to_xorgkbd[];
 extern const unsigned int code_map_qnum_to_xorgkbd_len;
 
-#define BUTTONS 9
+#define BUTTONS 11
 
 DeviceIntPtr vncKeyboardDev;
 DeviceIntPtr vncPointerDev;
@@ -206,8 +206,11 @@ static int vncPointerProc(DeviceIntPtr pDevice, int onoff)
 		btn_labels[4] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_WHEEL_DOWN);
 		btn_labels[5] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_HWHEEL_LEFT);
 		btn_labels[6] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_HWHEEL_RIGHT);
-		btn_labels[7] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_BACK);
-		btn_labels[8] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_FORWARD);
+		btn_labels[7] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_SIDE);
+   		btn_labels[8] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_EXTRA);
+    	btn_labels[9] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_FORWARD);
+    	btn_labels[10] = XIGetKnownProperty(BTN_LABEL_PROP_BTN_BACK);
+
 
 
 		axes_labels[0] = XIGetKnownProperty(AXIS_LABEL_PROP_REL_X);
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index 818cea679..94cde1b50 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -606,10 +606,13 @@ int Viewport::handle(int event)
     if (Fl::event_button3())
       buttonMask |= 4;
 
-    if(Fl::event_buttons()&FL_BUTTON(4))
-        buttonMask |= 128;
-    if(Fl::event_buttons()&FL_BUTTON(5))
-        buttonMask |= 256;
+    //Fl::event_button is only good for FL_PUSH and FL_RELEASE
+    if(event == FL_PUSH) {
+      if (Fl::event_button() == 8) //Mouse Back
+        buttonMask |= 1024;
+      if (Fl::event_button() == 9) //Mouse Forward
+        buttonMask |= 512;
+    }
 
     if (event == FL_MOUSEWHEEL) {
       wheelMask = 0;