diff --git a/widget/tests/test_keycodes.xul b/widget/tests/test_keycodes.xul
index 64a0580052e..fb49bef369b 100644
--- a/widget/tests/test_keycodes.xul
+++ b/widget/tests/test_keycodes.xul
@@ -91,6 +91,7 @@ if (IS_MAC) {
     "US":0x409,
     "German":0x407,
     "Greek":0x408,
+    "Spanish":0x40a,
     "French":0x40c,
     "Swedish":0x41d,
     "Arabic":0x401,
@@ -248,13 +249,18 @@ function runKeyEventTests()
     var expectEventTypeList = [];
     if (aShouldDelivedEvent & SHOULD_DELIVER_KEYDOWN)
       expectEventTypeList.push("keydown");
-    if (aShouldDelivedEvent & SHOULD_DELIVER_KEYPRESS)
+    if (aShouldDelivedEvent & SHOULD_DELIVER_KEYPRESS) {
       expectEventTypeList.push("keypress");
+      for (var i = 1; i < aExpectGeckoChar.length; i++) {
+        expectEventTypeList.push("keypress");
+      }
+    }
     if (aShouldDelivedEvent & SHOULD_DELIVER_KEYUP)
       expectEventTypeList.push("keyup");
     is(eventList.length, expectEventTypeList.length, name + ", wrong number of key events");
 
     var longerLength = Math.max(eventList.length, expectEventTypeList.length);
+    var keypressCount = 0;
     for (var i = 0; i < longerLength; i++) {
       var firedEventType = i < eventList.length ? eventList[i].type : "";
       var expectEventType = i < expectEventTypeList.length ? expectEventTypeList[i] : "";
@@ -271,7 +277,7 @@ function runKeyEventTests()
         is(e.shiftKey, aEvent.shift || aEvent.shiftRight || 0, name + ", Shift mismatch");
 
         if (aExpectGeckoChar.length > 0 && e.type == "keypress") {
-          is(e.charCode, aExpectGeckoChar.charCodeAt(0), name + ", charcode");
+          is(e.charCode, aExpectGeckoChar.charCodeAt(keypressCount++), name + ", charcode");
           if (aExpectedGeckoKeyCode >= 0) {
             if (aExpectGeckoChar) {
               is(e.keyCode, 0, name + ", wrong keycode");
@@ -1761,9 +1767,9 @@ function runKeyEventTests()
     testKey({layout:"French", keyCode:187, shift:1, chars:"+"},
             nsIDOMKeyEvent.DOM_VK_EQUALS, "+", SHOULD_DELIVER_ALL);
     //testKey({layout:"French", keyCode:221, chars:""},
-    //        0, "", SHOULD_DELIVER_KEYDOWN_KEYUP); // Dead-key
+    //        nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP); // Dead-key
     //testKey({layout:"French", keyCode:221, shift:1, chars:""},
-    //        0, "", SHOULD_DELIVER_KEYDOWN_KEYUP); // Dead-key
+    //        nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_ALL); // Dead-key
     testKey({layout:"French", keyCode:186, chars:"$"},
             nsIDOMKeyEvent.DOM_VK_DOLLAR, "$", SHOULD_DELIVER_ALL);
     testKey({layout:"French", keyCode:186, shift:1, chars:"\u00A3"},
@@ -1884,6 +1890,127 @@ function runKeyEventTests()
             nsIDOMKeyEvent.DOM_VK_PIPE, "|", SHOULD_DELIVER_ALL);
     testKey({layout:"Norwegian", keyCode:220, shift:1, chars:"\u00A7"},
             nsIDOMKeyEvent.DOM_VK_PIPE, "\u00A7", SHOULD_DELIVER_ALL);
+
+    // Dead keys on any layouts
+    testKey({layout:"French", keyCode:221, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:221, chars:"^^"},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "^^", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:65, chars:"\u00E2"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E2", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:65, shift:1, chars:"\u00C2"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C2", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:81, chars:"^q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "^q", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:221, shift:1, chars:"\u00A8\u00A8"},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "\u00A8\u00A8", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:65, shift:1, chars:"\u00C4"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C4", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:65, chars:"\u00E4"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E4", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"French", keyCode:221, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_CIRCUMFLEX, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"French", keyCode:81, shift:1, chars:"\u00A8Q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "\u00A8Q", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:186, chars:"``"},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "``", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, chars:"\u00E0"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E0", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, shift:1, chars:"\u00C0"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C0", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:81, chars:"`q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "`q", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:186, shift:1, chars:"^^"},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "^^", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, shift:1, chars:"\u00C2"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C2", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, chars:"\u00E2"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E2", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:186, shift:1, chars:""},
+            nsIDOMKeyEvent.DOM_VK_BACK_QUOTE, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:81, shift:1, chars:"^Q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "^Q", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:222, chars:"\u00B4\u00B4"},
+            0, "\u00B4\u00B4", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, chars:"\u00E1"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E1", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, shift:1, chars:"\u00C1"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C1", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:81, chars:"\u00B4q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "\u00B4q", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, shift:1, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:222, shift:1, chars:"\u00A8\u00A8"},
+            0, "\u00A8\u00A8", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, shift:1, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, shift:1, chars:"\u00C4"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00C4", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, shift:1, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:65, chars:"\u00E4"},
+            nsIDOMKeyEvent.DOM_VK_A, "\u00E4", SHOULD_DELIVER_ALL);
+
+    testKey({layout:"Spanish", keyCode:222, shift:1, chars:""},
+            0, "", SHOULD_DELIVER_KEYDOWN_KEYUP);
+    testKey({layout:"Spanish", keyCode:81, shift:1, chars:"\u00A8Q"},
+            nsIDOMKeyEvent.DOM_VK_Q, "\u00A8Q", SHOULD_DELIVER_ALL);
   }
 
   document.removeEventListener("keydown",  onKeyEvent, false);
diff --git a/widget/windows/KeyboardLayout.cpp b/widget/windows/KeyboardLayout.cpp
index d595364a0d0..9a0b594f75a 100644
--- a/widget/windows/KeyboardLayout.cpp
+++ b/widget/windows/KeyboardLayout.cpp
@@ -513,7 +513,7 @@ NativeKey::GetKeyLocation() const
  *****************************************************************************/
 
 KeyboardLayout::KeyboardLayout() :
-  mKeyboardLayout(0)
+  mKeyboardLayout(0), mPendingKeyboardLayout(0)
 {
   mDeadKeyTableListHead = nsnull;
 
@@ -550,6 +550,10 @@ UniCharsAndModifiers
 KeyboardLayout::OnKeyDown(PRUint8 aVirtualKey,
                           const ModifierKeyState& aModKeyState)
 {
+  if (mPendingKeyboardLayout) {
+    LoadLayout(mPendingKeyboardLayout);
+  }
+
   PRInt32 virtualKeyIndex = GetKeyIndex(aVirtualKey);
 
   if (virtualKeyIndex < 0) {
@@ -626,8 +630,15 @@ KeyboardLayout::GetUniCharsAndModifiers(
 }
 
 void
-KeyboardLayout::LoadLayout(HKL aLayout)
+KeyboardLayout::LoadLayout(HKL aLayout, bool aLoadLater)
 {
+  if (aLoadLater) {
+    mPendingKeyboardLayout = aLayout;
+    return;
+  }
+
+  mPendingKeyboardLayout = 0;
+
   if (mKeyboardLayout == aLayout) {
     return;
   }
diff --git a/widget/windows/KeyboardLayout.h b/widget/windows/KeyboardLayout.h
index 4746412f6b4..701d64d766f 100644
--- a/widget/windows/KeyboardLayout.h
+++ b/widget/windows/KeyboardLayout.h
@@ -8,6 +8,7 @@
 
 #include "nscore.h"
 #include "nsEvent.h"
+#include "nsString.h"
 #include <windows.h>
 
 #define NS_NUM_OF_KEYS          68
@@ -135,6 +136,8 @@ struct UniCharsAndModifiers
 
   bool UniCharsEqual(const UniCharsAndModifiers& aOther) const;
   bool UniCharsCaseInsensitiveEqual(const UniCharsAndModifiers& aOther) const;
+
+  nsString ToString() const { return nsString(mChars, mLength); }
 };
 
 struct DeadKeyEntry;
@@ -305,6 +308,7 @@ class KeyboardLayout
   };
 
   HKL mKeyboardLayout;
+  HKL mPendingKeyboardLayout;
 
   VirtualKey mVirtualKeys[NS_NUM_OF_KEYS];
   DeadKeyTableListEntry* mDeadKeyTableListHead;
@@ -357,11 +361,18 @@ public:
   UniCharsAndModifiers OnKeyDown(PRUint8 aVirtualKey,
                                  const ModifierKeyState& aModKeyState);
 
-  void LoadLayout(HKL aLayout);
+  /**
+   * LoadLayout() loads the keyboard layout.  If aLoadLater is true,
+   * it will be done when OnKeyDown() is called.
+   */
+  void LoadLayout(HKL aLayout, bool aLoadLater = false);
 
   PRUint32 ConvertNativeKeyCodeToDOMKeyCode(UINT aNativeKeyCode) const;
 
-  HKL GetLayout() const { return mKeyboardLayout; }
+  HKL GetLayout() const
+  {
+    return mPendingKeyboardLayout ? mPendingKeyboardLayout : mKeyboardLayout;
+  }
 };
 
 } // namespace widget
diff --git a/widget/windows/nsWindow.cpp b/widget/windows/nsWindow.cpp
index ac4698dbfc5..53e05ff7c1d 100644
--- a/widget/windows/nsWindow.cpp
+++ b/widget/windows/nsWindow.cpp
@@ -5653,10 +5653,26 @@ nsWindow::SynthesizeNativeKeyEvent(PRInt32 aNativeKeyboardLayout,
                                    const nsAString& aCharacters,
                                    const nsAString& aUnmodifiedCharacters)
 {
+  UINT keyboardLayoutListCount = ::GetKeyboardLayoutList(0, NULL);
+  NS_ASSERTION(keyboardLayoutListCount > 0,
+               "One keyboard layout must be installed at least");
+  HKL keyboardLayoutListBuff[50];
+  HKL* keyboardLayoutList =
+    keyboardLayoutListCount < 50 ? keyboardLayoutListBuff :
+                                   new HKL[keyboardLayoutListCount];
+  keyboardLayoutListCount =
+    ::GetKeyboardLayoutList(keyboardLayoutListCount, keyboardLayoutList);
+  NS_ASSERTION(keyboardLayoutListCount > 0,
+               "Failed to get all keyboard layouts installed on the system");
+
   nsPrintfCString layoutName("%08x", aNativeKeyboardLayout);
   HKL loadedLayout = LoadKeyboardLayoutA(layoutName.get(), KLF_NOTELLSHELL);
-  if (loadedLayout == NULL)
+  if (loadedLayout == NULL) {
+    if (keyboardLayoutListBuff != keyboardLayoutList) {
+      delete [] keyboardLayoutList;
+    }
     return NS_ERROR_NOT_AVAILABLE;
+  }
 
   // Setup clean key state and load desired layout
   BYTE originalKbdState[256];
@@ -5694,9 +5710,30 @@ nsWindow::SynthesizeNativeKeyEvent(PRInt32 aNativeKeyboardLayout,
       lParam |= 0x1000000;
     }
     MSG msg = WinUtils::InitMSG(WM_KEYDOWN, key, lParam);
-    if (i == keySequence.Length() - 1 && aCharacters.Length() > 0) {
-      nsFakeCharMessage fakeMsg = { aCharacters.CharAt(0), scanCode };
-      OnKeyDown(msg, modKeyState, nsnull, &fakeMsg);
+    if (i == keySequence.Length() - 1) {
+      bool makeDeadCharMessage =
+        gKbdLayout.IsDeadKey(key, modKeyState) && aCharacters.IsEmpty();
+      nsAutoString chars(aCharacters);
+      if (makeDeadCharMessage) {
+        UniCharsAndModifiers deadChars =
+          gKbdLayout.GetUniCharsAndModifiers(key, modKeyState);
+        chars = deadChars.ToString();
+        NS_ASSERTION(chars.Length() == 1,
+                     "Dead char must be only one character");
+      }
+      if (chars.IsEmpty()) {
+        OnKeyDown(msg, modKeyState, nsnull, nsnull);
+      } else {
+        nsFakeCharMessage fakeMsg = { chars.CharAt(0), scanCode,
+                                      makeDeadCharMessage };
+        OnKeyDown(msg, modKeyState, nsnull, &fakeMsg);
+        for (PRUint32 j = 1; j < chars.Length(); j++) {
+          nsFakeCharMessage fakeMsg = { chars.CharAt(j), scanCode, false };
+          MSG msg = fakeMsg.GetCharMessage(mWnd);
+          NativeKey nativeKey(gKbdLayout, this, msg);
+          OnChar(msg, nativeKey, modKeyState, nsnull);
+        }
+      }
     } else {
       OnKeyDown(msg, modKeyState, nsnull, nsnull);
     }
@@ -5724,9 +5761,21 @@ nsWindow::SynthesizeNativeKeyEvent(PRInt32 aNativeKeyboardLayout,
 
   // Restore old key state and layout
   ::SetKeyboardState(originalKbdState);
-  gKbdLayout.LoadLayout(oldLayout);
+  gKbdLayout.LoadLayout(oldLayout, true);
 
-  UnloadKeyboardLayout(loadedLayout);
+  // Don't unload the layout if it's installed actually.
+  for (PRUint32 i = 0; i < keyboardLayoutListCount; i++) {
+    if (keyboardLayoutList[i] == loadedLayout) {
+      loadedLayout = 0;
+      break;
+    }
+  }
+  if (keyboardLayoutListBuff != keyboardLayoutList) {
+    delete [] keyboardLayoutList;
+  }
+  if (loadedLayout) {
+    ::UnloadKeyboardLayout(loadedLayout);
+  }
   return NS_OK;
 }
 
@@ -6358,6 +6407,9 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
             msg.message == WM_CHAR || msg.message == WM_SYSCHAR || msg.message == WM_DEADCHAR)) {
     if (aFakeCharMessage) {
       MSG msg = aFakeCharMessage->GetCharMessage(mWnd);
+      if (msg.message == WM_DEADCHAR) {
+        return false;
+      }
       return OnChar(msg, nativeKey, aModKeyState, nsnull, extraFlags);
     }
 
diff --git a/widget/windows/nsWindowDefs.h b/widget/windows/nsWindowDefs.h
index bfa3e59088d..7d57cd1a1ab 100644
--- a/widget/windows/nsWindowDefs.h
+++ b/widget/windows/nsWindowDefs.h
@@ -211,12 +211,13 @@ struct nsAlternativeCharCode; // defined in nsGUIEvent.h
 struct nsFakeCharMessage {
   UINT mCharCode;
   UINT mScanCode;
+  bool mIsDeadKey;
 
   MSG GetCharMessage(HWND aWnd)
   {
     MSG msg;
     msg.hwnd = aWnd;
-    msg.message = WM_CHAR;
+    msg.message = mIsDeadKey ? WM_DEADCHAR : WM_CHAR;
     msg.wParam = static_cast<WPARAM>(mCharCode);
     msg.lParam = static_cast<LPARAM>(mScanCode);
     msg.time = 0;