diff --git a/widget/windows/KeyboardLayout.cpp b/widget/windows/KeyboardLayout.cpp
index 1e0d22a97e56..43571fc1688e 100644
--- a/widget/windows/KeyboardLayout.cpp
+++ b/widget/windows/KeyboardLayout.cpp
@@ -355,12 +355,24 @@ KeyboardLayout::IsNumpadKey(PRUint8 aVirtualKey)
   return VK_NUMPAD0 <= aVirtualKey && aVirtualKey <= VK_DIVIDE;
 }
 
+bool
+KeyboardLayout::IsDeadKey(PRUint8 aVirtualKey,
+                          PRUint8 aShiftState) const
+{
+  PRInt32 virtualKeyIndex = GetKeyIndex(aVirtualKey);
+  if (virtualKeyIndex < 0) {
+    return false;
+  }
+
+  return mVirtualKeys[virtualKeyIndex].IsDeadKey(aShiftState);
+}
+
 void
 KeyboardLayout::OnKeyDown(PRUint8 aVirtualKey)
 {
-  mLastVirtualKeyIndex = GetKeyIndex(aVirtualKey);
+  PRInt32 virtualKeyIndex = GetKeyIndex(aVirtualKey);
 
-  if (mLastVirtualKeyIndex < 0) {
+  if (virtualKeyIndex < 0) {
     // Does not produce any printable characters, but still preserves the
     // dead-key state.
     mNumOfChars = 0;
@@ -372,13 +384,13 @@ KeyboardLayout::OnKeyDown(PRUint8 aVirtualKey)
     return;
   }
 
-  mLastShiftState = GetShiftState(kbdState);
+  PRUint8 shiftState = GetShiftState(kbdState);
 
-  if (mVirtualKeys[mLastVirtualKeyIndex].IsDeadKey(mLastShiftState)) {
+  if (mVirtualKeys[virtualKeyIndex].IsDeadKey(shiftState)) {
     if (mActiveDeadKey < 0) {
       // Dead-key state activated. No characters generated.
       mActiveDeadKey = aVirtualKey;
-      mDeadKeyShiftState = mLastShiftState;
+      mDeadKeyShiftState = shiftState;
       mNumOfChars = 0;
       return;
     }
@@ -388,9 +400,8 @@ KeyboardLayout::OnKeyDown(PRUint8 aVirtualKey)
     PRInt32 activeDeadKeyIndex = GetKeyIndex(mActiveDeadKey);
     mVirtualKeys[activeDeadKeyIndex].GetUniChars(mDeadKeyShiftState,
                                                  mChars, mShiftStates);
-    mVirtualKeys[mLastVirtualKeyIndex].GetUniChars(mLastShiftState,
-                                                   &mChars[1],
-                                                   &mShiftStates[1]);
+    mVirtualKeys[virtualKeyIndex].GetUniChars(shiftState, &mChars[1],
+                                              &mShiftStates[1]);
     mNumOfChars = 2;
     DeactivateDeadKeyState();
     return;
@@ -399,8 +410,8 @@ KeyboardLayout::OnKeyDown(PRUint8 aVirtualKey)
   PRUint8 finalShiftState;
   PRUnichar uniChars[5];
   PRUint32 numOfBaseChars =
-    mVirtualKeys[mLastVirtualKeyIndex].GetUniChars(mLastShiftState, uniChars,
-                                                   &finalShiftState);
+    mVirtualKeys[virtualKeyIndex].GetUniChars(shiftState, uniChars,
+                                              &finalShiftState);
   if (mActiveDeadKey < 0) {
     // No dead-keys are active. Just return the produced characters.
     memcpy(mChars, uniChars, numOfBaseChars * sizeof(PRUnichar));
@@ -560,6 +571,19 @@ KeyboardLayout::LoadLayout(HKL aLayout)
 }
 
 
+// static
+PRUint8
+KeyboardLayout::GetShiftState(const nsModifierKeyState& aModifierKeyState)
+{
+  bool isShift = !!aModifierKeyState.mIsShiftDown;
+  bool isCtrl  = !!aModifierKeyState.mIsControlDown;
+  bool isAlt   = !!aModifierKeyState.mIsAltDown;
+  bool isCaps  = !!aModifierKeyState.mIsCapsLocked;
+
+  return ((isCaps << 3) | (isAlt << 2) | (isCtrl << 1) | isShift);
+}
+
+// static
 PRUint8
 KeyboardLayout::GetShiftState(const PBYTE aKbdState)
 {
diff --git a/widget/windows/KeyboardLayout.h b/widget/windows/KeyboardLayout.h
index 3188e7202596..f2d8e7b8a6da 100644
--- a/widget/windows/KeyboardLayout.h
+++ b/widget/windows/KeyboardLayout.h
@@ -27,6 +27,7 @@
 #define VK_OEM_CLEAR            0xFE
 
 class nsWindow;
+struct nsModifierKeyState;
 
 namespace mozilla {
 namespace widget {
@@ -162,8 +163,6 @@ class KeyboardLayout
   DeadKeyTableListEntry* mDeadKeyTableListHead;
   PRInt32 mActiveDeadKey;                 // -1 = no active dead-key
   PRUint8 mDeadKeyShiftState;
-  PRInt32 mLastVirtualKeyIndex;
-  PRUint8 mLastShiftState;
   PRUnichar mChars[5];                    // Dead-key + up to 4 characters
   PRUint8 mShiftStates[5];
   PRUint8 mNumOfChars;
@@ -191,14 +190,18 @@ public:
   KeyboardLayout();
   ~KeyboardLayout();
 
+  /**
+   * GetShiftState() returns shift state for aModifierKeyState.
+   */
+  static PRUint8 GetShiftState(const nsModifierKeyState& aModifierKeyState);
+
   static bool IsPrintableCharKey(PRUint8 aVirtualKey);
   static bool IsNumpadKey(PRUint8 aVirtualKey);
 
-  bool IsDeadKey() const
-  {
-    return (mLastVirtualKeyIndex >= 0) ?
-      mVirtualKeys[mLastVirtualKeyIndex].IsDeadKey(mLastShiftState) : false;
-  }
+  /**
+   * IsDeadKey() returns true if aVirtualKey is a dead key with aShiftState.
+   */
+  bool IsDeadKey(PRUint8 aVirtualKey, PRUint8 aShiftState) const;
 
   void LoadLayout(HKL aLayout);
   void OnKeyDown(PRUint8 aVirtualKey);
diff --git a/widget/windows/nsWindow.cpp b/widget/windows/nsWindow.cpp
index 58abcf7f3852..e4f638970923 100644
--- a/widget/windows/nsWindow.cpp
+++ b/widget/windows/nsWindow.cpp
@@ -6322,6 +6322,8 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
       return noDefault;
   }
 
+  PRUint8 currentShiftState = KeyboardLayout::GetShiftState(aModKeyState);
+  bool isDeadKey = gKbdLayout.IsDeadKey(virtualKeyCode, currentShiftState);
   PRUint32 extraFlags = (noDefault ? NS_EVENT_FLAG_NO_DEFAULT : 0);
   MSG msg;
   BOOL gotMsg = aFakeCharMessage ||
@@ -6330,7 +6332,7 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
   // confusion between ctrl-enter and ctrl-J.
   if (DOMKeyCode == NS_VK_RETURN || DOMKeyCode == NS_VK_BACK ||
       ((aModKeyState.mIsControlDown || aModKeyState.mIsAltDown)
-       && !gKbdLayout.IsDeadKey() && KeyboardLayout::IsPrintableCharKey(virtualKeyCode)))
+       && !isDeadKey && KeyboardLayout::IsPrintableCharKey(virtualKeyCode)))
   {
     // Remove a possible WM_CHAR or WM_SYSCHAR messages from the message queue.
     // They can be more than one because of:
@@ -6405,8 +6407,9 @@ LRESULT nsWindow::OnKeyDown(const MSG &aMsg,
     return PluginHasFocus() && noDefault;
   }
 
-  if (gKbdLayout.IsDeadKey ())
+  if (isDeadKey) {
     return PluginHasFocus() && noDefault;
+  }
 
   PRUint8 shiftStates[5];
   PRUnichar uniChars[5];