diff --git a/mozilla/content/html/style/src/nsCSSLoader.cpp b/mozilla/content/html/style/src/nsCSSLoader.cpp
index f84cfe8a838..5661d92b788 100644
--- a/mozilla/content/html/style/src/nsCSSLoader.cpp
+++ b/mozilla/content/html/style/src/nsCSSLoader.cpp
@@ -312,6 +312,8 @@ public:
   nsVoidArray   mPendingDocSheets;  // loaded sheet waiting for doc insertion
   nsVoidArray   mPendingAlternateSheets;  // alternates waiting for load to start
 
+  nsHashtable   mSheetMapTable;  // map to insertion index arrays
+
   // @charset support
   nsString      mCharset;        // the charset we are using
 
@@ -484,6 +486,13 @@ static PRBool PR_CALLBACK DeleteLoadData(void* aData, void* aClosure)
   return PR_TRUE;
 }
 
+static PRBool PR_CALLBACK DeleteSheetMap(nsHashKey* aKey, void* aData, void* aClosure)
+{
+  nsAutoVoidArray* map = (nsAutoVoidArray*)aData;
+  delete map;
+  return PR_TRUE;
+}
+
 CSSLoaderImpl::~CSSLoaderImpl(void)
 {
   if (mLoadingSheets.Count() > 0) {
@@ -494,6 +503,7 @@ CSSLoaderImpl::~CSSLoaderImpl(void)
   mLoadingSheets.Enumerate(DeleteHashLoadData);
   mPendingDocSheets.EnumerateForwards(DeletePendingData, nsnull);
   mPendingAlternateSheets.EnumerateForwards(DeleteLoadData, nsnull);
+  mSheetMapTable.Enumerate(DeleteSheetMap);
 }
 
 NS_IMPL_ISUPPORTS1(CSSLoaderImpl, nsICSSLoader)
@@ -1109,7 +1119,7 @@ CSSLoaderImpl::InsertSheetInDoc(nsICSSStyleSheet* aSheet, PRInt32 aDocIndex,
     return NS_ERROR_NULL_POINTER;
   }
 
-  if (aElement) {
+  if (nsnull != aElement) {
     nsIDOMNode* domNode = nsnull;
     if (NS_SUCCEEDED(aElement->QueryInterface(NS_GET_IID(nsIDOMNode), (void**)&domNode))) {
       aSheet->SetOwningNode(domNode);
@@ -1128,11 +1138,37 @@ CSSLoaderImpl::InsertSheetInDoc(nsICSSStyleSheet* aSheet, PRInt32 aDocIndex,
   aSheet->GetTitle(title);
   aSheet->SetEnabled(! IsAlternate(title));
 
-  mDocument->InsertStyleSheetAt(aSheet, aDocIndex, aNotify);
-  if (aObserver) {
-    aObserver->StyleSheetLoaded(aSheet, aNotify);
+  nsVoidKey key(mDocument);
+  nsAutoVoidArray*  sheetMap = (nsAutoVoidArray*)mSheetMapTable.Get(&key);
+  if (! sheetMap) {
+    sheetMap = new nsAutoVoidArray();
+    if (sheetMap) {
+      mSheetMapTable.Put(&key, sheetMap);
+    }
   }
-  return NS_OK;
+
+  if (sheetMap) {
+    PRInt32 insertIndex = sheetMap->Count();
+    PRBool insertedSheet = PR_FALSE;
+    while (0 <= --insertIndex) {
+      PRInt32 targetIndex = NS_PTR_TO_INT32(sheetMap->ElementAt(insertIndex));
+      if (targetIndex < aDocIndex) {
+        mDocument->InsertStyleSheetAt(aSheet, insertIndex + 1, aNotify);
+        sheetMap->InsertElementAt((void*)aDocIndex, insertIndex + 1);
+        insertedSheet = PR_TRUE;
+        break;
+      }
+    }
+    if (!insertedSheet) { // didn't insert yet
+      mDocument->InsertStyleSheetAt(aSheet, 0, aNotify);
+      sheetMap->InsertElementAt((void*)aDocIndex, 0);
+    }
+    if (nsnull != aObserver) {
+      aObserver->StyleSheetLoaded(aSheet, aNotify);
+    }
+    return NS_OK;
+  }
+  return NS_ERROR_OUT_OF_MEMORY;
 }
 
 nsresult
@@ -1143,8 +1179,33 @@ CSSLoaderImpl::InsertChildSheet(nsICSSStyleSheet* aSheet, nsICSSStyleSheet* aPar
     return NS_ERROR_NULL_POINTER;
   }
 
-  aParentSheet->InsertStyleSheetAt(aSheet, aIndex);
-  return NS_OK;
+  nsVoidKey key(aParentSheet);
+  nsAutoVoidArray*  sheetMap = (nsAutoVoidArray*)mSheetMapTable.Get(&key);
+  if (! sheetMap) {
+    sheetMap = new nsAutoVoidArray();
+    if (sheetMap) {
+      mSheetMapTable.Put(&key, sheetMap);
+    }
+  }
+
+  if (sheetMap) {
+    PRInt32 insertIndex = sheetMap->Count();
+    while (0 <= --insertIndex) {
+      PRInt32 targetIndex = NS_PTR_TO_INT32(sheetMap->ElementAt(insertIndex));
+      if (targetIndex < aIndex) {
+        aParentSheet->InsertStyleSheetAt(aSheet, insertIndex + 1);
+        sheetMap->InsertElementAt((void*)aIndex, insertIndex + 1);
+        aSheet = nsnull;
+        break;
+      }
+    }
+    if (nsnull != aSheet) { // didn't insert yet
+      aParentSheet->InsertStyleSheetAt(aSheet, 0);
+      sheetMap->InsertElementAt((void*)aIndex, 0);
+    }
+    return NS_OK;
+  }
+  return NS_ERROR_OUT_OF_MEMORY;
 }
 
 nsresult
diff --git a/mozilla/layout/style/nsCSSLoader.cpp b/mozilla/layout/style/nsCSSLoader.cpp
index f84cfe8a838..5661d92b788 100644
--- a/mozilla/layout/style/nsCSSLoader.cpp
+++ b/mozilla/layout/style/nsCSSLoader.cpp
@@ -312,6 +312,8 @@ public:
   nsVoidArray   mPendingDocSheets;  // loaded sheet waiting for doc insertion
   nsVoidArray   mPendingAlternateSheets;  // alternates waiting for load to start
 
+  nsHashtable   mSheetMapTable;  // map to insertion index arrays
+
   // @charset support
   nsString      mCharset;        // the charset we are using
 
@@ -484,6 +486,13 @@ static PRBool PR_CALLBACK DeleteLoadData(void* aData, void* aClosure)
   return PR_TRUE;
 }
 
+static PRBool PR_CALLBACK DeleteSheetMap(nsHashKey* aKey, void* aData, void* aClosure)
+{
+  nsAutoVoidArray* map = (nsAutoVoidArray*)aData;
+  delete map;
+  return PR_TRUE;
+}
+
 CSSLoaderImpl::~CSSLoaderImpl(void)
 {
   if (mLoadingSheets.Count() > 0) {
@@ -494,6 +503,7 @@ CSSLoaderImpl::~CSSLoaderImpl(void)
   mLoadingSheets.Enumerate(DeleteHashLoadData);
   mPendingDocSheets.EnumerateForwards(DeletePendingData, nsnull);
   mPendingAlternateSheets.EnumerateForwards(DeleteLoadData, nsnull);
+  mSheetMapTable.Enumerate(DeleteSheetMap);
 }
 
 NS_IMPL_ISUPPORTS1(CSSLoaderImpl, nsICSSLoader)
@@ -1109,7 +1119,7 @@ CSSLoaderImpl::InsertSheetInDoc(nsICSSStyleSheet* aSheet, PRInt32 aDocIndex,
     return NS_ERROR_NULL_POINTER;
   }
 
-  if (aElement) {
+  if (nsnull != aElement) {
     nsIDOMNode* domNode = nsnull;
     if (NS_SUCCEEDED(aElement->QueryInterface(NS_GET_IID(nsIDOMNode), (void**)&domNode))) {
       aSheet->SetOwningNode(domNode);
@@ -1128,11 +1138,37 @@ CSSLoaderImpl::InsertSheetInDoc(nsICSSStyleSheet* aSheet, PRInt32 aDocIndex,
   aSheet->GetTitle(title);
   aSheet->SetEnabled(! IsAlternate(title));
 
-  mDocument->InsertStyleSheetAt(aSheet, aDocIndex, aNotify);
-  if (aObserver) {
-    aObserver->StyleSheetLoaded(aSheet, aNotify);
+  nsVoidKey key(mDocument);
+  nsAutoVoidArray*  sheetMap = (nsAutoVoidArray*)mSheetMapTable.Get(&key);
+  if (! sheetMap) {
+    sheetMap = new nsAutoVoidArray();
+    if (sheetMap) {
+      mSheetMapTable.Put(&key, sheetMap);
+    }
   }
-  return NS_OK;
+
+  if (sheetMap) {
+    PRInt32 insertIndex = sheetMap->Count();
+    PRBool insertedSheet = PR_FALSE;
+    while (0 <= --insertIndex) {
+      PRInt32 targetIndex = NS_PTR_TO_INT32(sheetMap->ElementAt(insertIndex));
+      if (targetIndex < aDocIndex) {
+        mDocument->InsertStyleSheetAt(aSheet, insertIndex + 1, aNotify);
+        sheetMap->InsertElementAt((void*)aDocIndex, insertIndex + 1);
+        insertedSheet = PR_TRUE;
+        break;
+      }
+    }
+    if (!insertedSheet) { // didn't insert yet
+      mDocument->InsertStyleSheetAt(aSheet, 0, aNotify);
+      sheetMap->InsertElementAt((void*)aDocIndex, 0);
+    }
+    if (nsnull != aObserver) {
+      aObserver->StyleSheetLoaded(aSheet, aNotify);
+    }
+    return NS_OK;
+  }
+  return NS_ERROR_OUT_OF_MEMORY;
 }
 
 nsresult
@@ -1143,8 +1179,33 @@ CSSLoaderImpl::InsertChildSheet(nsICSSStyleSheet* aSheet, nsICSSStyleSheet* aPar
     return NS_ERROR_NULL_POINTER;
   }
 
-  aParentSheet->InsertStyleSheetAt(aSheet, aIndex);
-  return NS_OK;
+  nsVoidKey key(aParentSheet);
+  nsAutoVoidArray*  sheetMap = (nsAutoVoidArray*)mSheetMapTable.Get(&key);
+  if (! sheetMap) {
+    sheetMap = new nsAutoVoidArray();
+    if (sheetMap) {
+      mSheetMapTable.Put(&key, sheetMap);
+    }
+  }
+
+  if (sheetMap) {
+    PRInt32 insertIndex = sheetMap->Count();
+    while (0 <= --insertIndex) {
+      PRInt32 targetIndex = NS_PTR_TO_INT32(sheetMap->ElementAt(insertIndex));
+      if (targetIndex < aIndex) {
+        aParentSheet->InsertStyleSheetAt(aSheet, insertIndex + 1);
+        sheetMap->InsertElementAt((void*)aIndex, insertIndex + 1);
+        aSheet = nsnull;
+        break;
+      }
+    }
+    if (nsnull != aSheet) { // didn't insert yet
+      aParentSheet->InsertStyleSheetAt(aSheet, 0);
+      sheetMap->InsertElementAt((void*)aIndex, 0);
+    }
+    return NS_OK;
+  }
+  return NS_ERROR_OUT_OF_MEMORY;
 }
 
 nsresult