diff --git a/mozilla/content/html/document/src/nsHTMLContentSink.cpp b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
index a4a0c931c87..a95df350160 100644
--- a/mozilla/content/html/document/src/nsHTMLContentSink.cpp
+++ b/mozilla/content/html/document/src/nsHTMLContentSink.cpp
@@ -93,6 +93,7 @@
 #include "nsITimer.h"
 #include "nsITimerCallback.h"
 #include "nsDOMError.h"
+#include "nsIScrollable.h"
 
 #ifdef ALLOW_ASYNCH_STYLE_SHEETS
 const PRBool kBlock=PR_FALSE;
@@ -3023,11 +3024,19 @@ HTMLContentSink::StartLayout()
   mLastNotificationTime = PR_Now();
 
   // If it's a frameset document then disable scrolling.
-  // Scrolling was reset nsWebShell::LoadURL() by InitFrameData()
+  // Else, reset scrolling to default settings for this shell.
+  // This must happen before the initial reflow, when we create the root frame
+  nsresult rv;
   if (mWebShell) {
-    if (mFrameset) {
-      mWebShell->SetScrolling(NS_STYLE_OVERFLOW_HIDDEN, PR_FALSE);
-    } 
+    nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(mWebShell, &rv);
+    if (NS_SUCCEEDED(rv) && scrollableContainer) {
+      if (mFrameset) {
+        scrollableContainer->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y, NS_STYLE_OVERFLOW_HIDDEN);
+        scrollableContainer->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X, NS_STYLE_OVERFLOW_HIDDEN);
+      } else {
+        scrollableContainer->ResetScrollbarPreferences();
+      }
+    }
   }
 
   PRInt32 i, ns = mDocument->GetNumberOfShells();
@@ -3057,7 +3066,7 @@ HTMLContentSink::StartLayout()
   // frameset document, disable the scroll bars on the views.
   char* ref = nsnull;           // init in case mDocumentURI is not a url
   nsIURL* url;
-  nsresult rv = mDocumentURI->QueryInterface(NS_GET_IID(nsIURL), (void**)&url);
+  rv = mDocumentURI->QueryInterface(NS_GET_IID(nsIURL), (void**)&url);
   if (NS_SUCCEEDED(rv)) {
     rv = url->GetRef(&ref);
     NS_RELEASE(url);
diff --git a/mozilla/docshell/base/nsDocShell.cpp b/mozilla/docshell/base/nsDocShell.cpp
index 4d14c113015..bffe563cec4 100644
--- a/mozilla/docshell/base/nsDocShell.cpp
+++ b/mozilla/docshell/base/nsDocShell.cpp
@@ -40,6 +40,7 @@
 #include "nsIChromeEventHandler.h"
 #include "nsIDOMWindow.h"
 #include "nsIWebBrowserChrome.h"
+#include "nsPoint.h"
 
 // Interfaces Needed
 #include "nsIGlobalHistory.h"
@@ -69,7 +70,9 @@ nsDocShell::nsDocShell() :
   mInitialPageLoad(PR_TRUE),
   mParent(nsnull),
   mTreeOwner(nsnull),
-  mChromeEventHandler(nsnull)
+  mChromeEventHandler(nsnull),
+  mCurrentScrollbarPref(-1,-1),
+  mDefaultScrollbarPref(-1,-1)
 {
   NS_INIT_REFCNT();
 }
@@ -270,8 +273,6 @@ nsDocShell::SetDocument(nsIDOMDocument *aDOMDoc, nsIDOMElement *aRootNode)
    doc->SetRootContent(rootContent);
 
    // (6) reflow the document
-   //XXX: SetScrolling doesn't make any sense
-   //SetScrolling(-1, PR_FALSE);
    PRInt32 i;
    PRInt32 ns = doc->GetNumberOfShells();
    for (i = 0; i < ns; i++) 
@@ -1575,41 +1576,109 @@ NS_IMETHODIMP nsDocShell::SetScrollRangeEx(PRInt32 minHorizontalPos,
    return NS_ERROR_FAILURE;
 }
 
-NS_IMETHODIMP nsDocShell::GetScrollbarPreferences(PRInt32 scrollOrientation,
+// Get scroll setting for this document only
+//
+// One important client is nsCSSFrameConstructor::ConstructRootFrame()
+NS_IMETHODIMP nsDocShell::GetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
    PRInt32* scrollbarPref)
 {
    NS_ENSURE_ARG_POINTER(scrollbarPref);
+   switch(scrollOrientation) {
+     case ScrollOrientation_X:
+       *scrollbarPref = mCurrentScrollbarPref.x;
+       return NS_OK;
 
-   nsCOMPtr<nsIScrollableView> scrollView;
-   NS_ENSURE_SUCCESS(GetRootScrollableView(getter_AddRefs(scrollView)), 
-      NS_ERROR_FAILURE);
+     case ScrollOrientation_Y:
+       *scrollbarPref = mCurrentScrollbarPref.y;
+       return NS_OK;
 
-   // XXX This is all evil, we need to convert.  We don't know our prefs
-   // are the same as this interfaces.
- /*  nsScrollPreference scrollPref;
-
-   NS_ENSURE_SUCCESS(scrollView->GetScrollPreference(scrollPref), 
-      NS_ERROR_FAILURE);
-
-   *scrollbarPref = scrollPref; */
-
-   return NS_OK;
+     default:
+       NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
+   }
+   return NS_ERROR_FAILURE;
 }
 
-NS_IMETHODIMP nsDocShell::SetScrollbarPreferences(PRInt32 scrollOrientation,
+// This returns setting for all documents in this webshell
+NS_IMETHODIMP nsDocShell::GetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
+   PRInt32* scrollbarPref)
+{
+   NS_ENSURE_ARG_POINTER(scrollbarPref);
+   switch(scrollOrientation) {
+     case ScrollOrientation_X:
+       *scrollbarPref = mDefaultScrollbarPref.x;
+       return NS_OK;
+
+     case ScrollOrientation_Y:
+       *scrollbarPref = mDefaultScrollbarPref.y;
+       return NS_OK;
+
+     default:
+       NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
+   }
+   return NS_ERROR_FAILURE;
+}
+
+// Set scrolling preference for this document only.
+//
+// There are three possible values stored in the shell:
+//  1) NS_STYLE_OVERFLOW_HIDDEN = no scrollbars
+//  2) NS_STYLE_OVERFLOW_AUTO = scrollbars appear if needed
+//  3) NS_STYLE_OVERFLOW_SCROLL = scrollbars always
+//
+// XXX Currently OVERFLOW_SCROLL isn't honored,
+//     as it is not implemented by Gfx scrollbars
+// XXX setting has no effect after the root frame is created
+//     as it is not implemented by Gfx scrollbars
+//
+// One important client is HTMLContentSink::StartLayout()
+NS_IMETHODIMP nsDocShell::SetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
    PRInt32 scrollbarPref)
 {
-   nsCOMPtr<nsIScrollableView> scrollView;
-   NS_ENSURE_SUCCESS(GetRootScrollableView(getter_AddRefs(scrollView)), 
-      NS_ERROR_FAILURE);
+   switch(scrollOrientation) {
+     case ScrollOrientation_X:
+       mCurrentScrollbarPref.x = scrollbarPref;
+       return NS_OK;
 
-   // XXX This is evil.  We should do a mapping, we don't know our prefs
-   // are the same as this interface.  In fact it doesn't compile
-  /* nsScrollPreference scrollPref = scrollbarPref;
-   NS_ENSURE_SUCCESS(scrollView->SetScrollPreference(scrollPref), 
-      NS_ERROR_FAILURE);  */
+     case ScrollOrientation_Y:
+       mCurrentScrollbarPref.y = scrollbarPref;
+       return NS_OK;
 
-   return NS_OK;
+     default:
+       NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
+   }
+   return NS_ERROR_FAILURE;
+}
+
+// Set scrolling preference for all documents in this shell
+// One important client is nsHTMLFrameInnerFrame::CreateWebShell()
+NS_IMETHODIMP nsDocShell::SetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
+   PRInt32 scrollbarPref)
+{
+   switch(scrollOrientation) {
+     case ScrollOrientation_X:
+       mDefaultScrollbarPref.x = scrollbarPref;
+       return NS_OK;
+
+     case ScrollOrientation_Y:
+       mDefaultScrollbarPref.y = scrollbarPref;
+       return NS_OK;
+
+     default:
+       NS_ENSURE_TRUE(PR_FALSE, NS_ERROR_INVALID_ARG);
+   }
+   return NS_ERROR_FAILURE;
+}
+
+// Reset 'current' scrollbar settings to 'default'.
+// This must be called before every document load or else
+// frameset scrollbar settings (e.g. <IFRAME SCROLLING="no">
+// will not be preserved.
+//
+// One important client is HTMLContentSink::StartLayout()
+NS_IMETHODIMP nsDocShell::ResetScrollbarPreferences()
+{
+  mCurrentScrollbarPref = mDefaultScrollbarPref;
+  return NS_OK;
 }
 
 NS_IMETHODIMP nsDocShell::GetScrollbarVisibility(PRBool* verticalVisible,
diff --git a/mozilla/docshell/base/nsDocShell.h b/mozilla/docshell/base/nsDocShell.h
index 24eb7f39b10..d65b196b4e4 100644
--- a/mozilla/docshell/base/nsDocShell.h
+++ b/mozilla/docshell/base/nsDocShell.h
@@ -47,6 +47,7 @@
 #include "nsIInterfaceRequestor.h"
 
 #include "nsDSURIContentListener.h"
+#include "nsPoint.h" // mCurrent/mDefaultScrollbarPreferences
 
 // Interfaces Needed
 #include "nsISHistory.h"
@@ -191,6 +192,8 @@ protected:
    PRInt32                    mMarginWidth;
    PRInt32                    mMarginHeight;
    PRInt32                    mItemType;
+   nsPoint                    mCurrentScrollbarPref; // this document only
+   nsPoint                    mDefaultScrollbarPref; // persistent across doc loads
    PRBool                     mUpdateHistoryOnLoad;
    PRBool                     mInitialPageLoad;
 
diff --git a/mozilla/docshell/base/nsIScrollable.idl b/mozilla/docshell/base/nsIScrollable.idl
index 55179aba41e..7f229a048ba 100644
--- a/mozilla/docshell/base/nsIScrollable.idl
+++ b/mozilla/docshell/base/nsIScrollable.idl
@@ -92,10 +92,16 @@ interface nsIScrollable : nsISupports
 	const long Scrollbar_Always = 3;
 
 	/*
-	Retrieves of Set the preferences for the scroll bar.
+	Retrieves or Set the preferences for the scroll bar.
+	current is 'scrolling preference for this document'
+	default is 'scrolling preference for all documents in this shell'
+	resetScrollbarPreferences resets current to default
 	*/
-	void getScrollbarPreferences(in long scrollOrientation, out long scrollbarPref);
-	void setScrollbarPreferences(in long scrollOrientation, in long scrollbarPref);
+	void getCurrentScrollbarPreferences(in long scrollOrientation, out long scrollbarPref);
+	void setCurrentScrollbarPreferences(in long scrollOrientation, in long scrollbarPref);
+	void getDefaultScrollbarPreferences(in long scrollOrientation, out long scrollbarPref);
+	void setDefaultScrollbarPreferences(in long scrollOrientation, in long scrollbarPref);
+	void resetScrollbarPreferences();
 
 	/*
 	Get information about whether the vertical and horizontal scrollbars are
diff --git a/mozilla/docshell/base/nsWebShell.cpp b/mozilla/docshell/base/nsWebShell.cpp
index 705a3234379..1a054087ae1 100644
--- a/mozilla/docshell/base/nsWebShell.cpp
+++ b/mozilla/docshell/base/nsWebShell.cpp
@@ -215,7 +215,6 @@ public:
   // nsIWebShell
   NS_IMETHOD Init(nsNativeWidget aNativeParent,
                   PRInt32 x, PRInt32 y, PRInt32 w, PRInt32 h,
-                  nsScrollPreference aScrolling = nsScrollPreference_kAuto,
                   PRBool aAllowPlugins = PR_TRUE,
                   PRBool aIsSunkenBorder = PR_FALSE);
   NS_IMETHOD SetContainer(nsIWebShellContainer* aContainer);
@@ -235,9 +234,6 @@ public:
   NS_IMETHOD FindChildWithName(const PRUnichar* aName,
                                nsIWebShell*& aResult);
 
-  NS_IMETHOD GetScrolling(PRInt32& aScrolling);
-  NS_IMETHOD SetScrolling(PRInt32 aScrolling, PRBool aSetCurrentAndInitial = PR_TRUE);
-
   // Document load api's
   NS_IMETHOD GetDocumentLoader(nsIDocumentLoader*& aResult);
   NS_IMETHOD LoadURL(const PRUnichar *aURLSpec,
@@ -375,7 +371,7 @@ public:
 
 protected:
   void GetRootWebShellEvenIfChrome(nsIWebShell** aResult);
-  void InitFrameData(PRBool aCompleteInitScrolling);
+  void InitFrameData();
   nsresult CheckForTrailingSlash(nsIURI* aURL);
   nsresult GetViewManager(nsIViewManager* *viewManager);
   nsresult InitDialogVars(void);
@@ -412,7 +408,6 @@ protected:
 
   nsScrollPreference mScrollPref;
 
-  PRInt32 mScrolling[2];
   nsVoidArray mRefreshments;
 
   eCharsetReloadState mCharsetReloadState;
@@ -585,7 +580,7 @@ nsWebShell::nsWebShell() : nsDocShell()
   mHistoryIndex = -1;
   mScrollPref = nsScrollPreference_kAuto;
   mThreadEventQueue = nsnull;
-  InitFrameData(PR_TRUE);
+  InitFrameData();
   mItemType = typeContent;
   mSHist = nsnull;
   mIsInSHist = PR_FALSE;
@@ -636,7 +631,7 @@ nsWebShell::~nsWebShell()
     mScriptContext = nsnull;
   }
 
-  InitFrameData(PR_TRUE);
+  InitFrameData();
 
   // Free up history memory
   PRInt32 i, n = mHistory.Count();
@@ -657,17 +652,10 @@ nsWebShell::~nsWebShell()
 #endif
 }
 
-void nsWebShell::InitFrameData(PRBool aCompleteInitScrolling)
+void nsWebShell::InitFrameData()
 {
-  if (aCompleteInitScrolling) {
-    mScrolling[0] = -1;
-    mScrolling[1] = -1;
-    SetMarginWidth(-1);    
-    SetMarginHeight(-1);
-  }
-  else {
-    mScrolling[1] = mScrolling[0];
-  }
+  SetMarginWidth(-1);    
+  SetMarginHeight(-1);
 }
 
 nsresult
@@ -754,6 +742,7 @@ NS_INTERFACE_MAP_BEGIN(nsWebShell)
    NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeItem)
    NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeNode)
    NS_INTERFACE_MAP_ENTRY(nsIWebNavigation)
+   NS_INTERFACE_MAP_ENTRY(nsIScrollable)
 NS_INTERFACE_MAP_END
 
 NS_IMETHODIMP
@@ -959,7 +948,6 @@ nsWebShell::HandleUnknownContentType(nsIDocumentLoader* loader,
 NS_IMETHODIMP
 nsWebShell::Init(nsNativeWidget aNativeParent,
                  PRInt32 x, PRInt32 y, PRInt32 w, PRInt32 h,
-                 nsScrollPreference aScrolling,
                  PRBool aAllowPlugins,
                  PRBool aIsSunkenBorder)
 {
@@ -990,8 +978,6 @@ nsWebShell::Init(nsNativeWidget aNativeParent,
 
   CreatePluginHost(aAllowPlugins);
 
-  //mScrollPref = aScrolling;
-
   WEB_TRACE(WEB_TRACE_CALLS,
             ("nsWebShell::Init: this=%p", this));
 
@@ -1306,24 +1292,6 @@ nsWebShell::FindChildWithName(const PRUnichar* aName1,
    return NS_OK;
 }
 
-NS_IMETHODIMP
-nsWebShell::GetScrolling(PRInt32& aScrolling)
-{
-  aScrolling = mScrolling[1];
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsWebShell::SetScrolling(PRInt32 aScrolling, PRBool aSetCurrentAndInitial)
-{
-  mScrolling[1] = aScrolling;
-  if (aSetCurrentAndInitial) {
-    mScrolling[0] = aScrolling;
-  }
-  return NS_OK;
-}
-
-
 /**
  * Document Load methods
  */
@@ -1389,11 +1357,6 @@ nsWebShell::LoadURL(const PRUnichar *aURLSpec,
                     nsISupports * aHistoryState,
                     const PRUnichar* aReferrer)
 {
-  // Initialize margnwidth, marginheight. Put scrolling back the way it was
-  // before the last document was loaded.
-
-  InitFrameData(PR_FALSE);
-
   const char *cmd = mViewSource ? "view-source" : "view" ;
 
   return LoadURL(aURLSpec, cmd, aPostDataStream,
@@ -3843,7 +3806,6 @@ NS_IMETHODIMP nsWebShell::SetDocument(nsIDOMDocument *aDOMDoc,
   rootContent->SetDocument(doc, PR_TRUE);
 
   // (6) reflow the document
-  InitFrameData(PR_FALSE);  // Reset the scrolling state to initial
   PRInt32 i;
   PRInt32 ns = doc->GetNumberOfShells();
   for (i = 0; i < ns; i++) 
diff --git a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
index ffecc91fb15..246d0d7823e 100644
--- a/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
+++ b/mozilla/embedding/browser/webBrowser/nsWebBrowser.cpp
@@ -865,7 +865,7 @@ NS_IMETHODIMP nsWebBrowser::SetScrollRangeEx(PRInt32 minHorizontalPos,
       minVerticalPos, maxVerticalPos);
 }
 
-NS_IMETHODIMP nsWebBrowser::GetScrollbarPreferences(PRInt32 scrollOrientation,
+NS_IMETHODIMP nsWebBrowser::GetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
    PRInt32* scrollbarPref)
 {
    NS_ENSURE_ARG_POINTER(scrollbarPref);
@@ -875,10 +875,23 @@ NS_IMETHODIMP nsWebBrowser::GetScrollbarPreferences(PRInt32 scrollOrientation,
 
    NS_ENSURE_TRUE(scroll, NS_ERROR_FAILURE);
 
-   return scroll->GetScrollbarPreferences(scrollOrientation, scrollbarPref);
+   return scroll->GetCurrentScrollbarPreferences(scrollOrientation, scrollbarPref);
 }
 
-NS_IMETHODIMP nsWebBrowser::SetScrollbarPreferences(PRInt32 scrollOrientation,
+NS_IMETHODIMP nsWebBrowser::GetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
+   PRInt32* scrollbarPref)
+{
+   NS_ENSURE_ARG_POINTER(scrollbarPref);
+   NS_ENSURE_STATE(mDocShell);
+
+   nsCOMPtr<nsIScrollable> scroll(do_QueryInterface(mDocShell));
+
+   NS_ENSURE_TRUE(scroll, NS_ERROR_FAILURE);
+
+   return scroll->GetDefaultScrollbarPreferences(scrollOrientation, scrollbarPref);
+}
+
+NS_IMETHODIMP nsWebBrowser::SetCurrentScrollbarPreferences(PRInt32 scrollOrientation,
    PRInt32 scrollbarPref)
 {
    NS_ENSURE_STATE(mDocShell);
@@ -887,7 +900,30 @@ NS_IMETHODIMP nsWebBrowser::SetScrollbarPreferences(PRInt32 scrollOrientation,
 
    NS_ENSURE_TRUE(scroll, NS_ERROR_FAILURE);
 
-   return scroll->SetScrollbarPreferences(scrollOrientation, scrollbarPref);
+   return scroll->SetCurrentScrollbarPreferences(scrollOrientation, scrollbarPref);
+}
+
+NS_IMETHODIMP nsWebBrowser::SetDefaultScrollbarPreferences(PRInt32 scrollOrientation,
+   PRInt32 scrollbarPref)
+{
+   NS_ENSURE_STATE(mDocShell);
+
+   nsCOMPtr<nsIScrollable> scroll(do_QueryInterface(mDocShell));
+
+   NS_ENSURE_TRUE(scroll, NS_ERROR_FAILURE);
+
+   return scroll->SetDefaultScrollbarPreferences(scrollOrientation, scrollbarPref);
+}
+
+NS_IMETHODIMP nsWebBrowser::ResetScrollbarPreferences()
+{
+   NS_ENSURE_STATE(mDocShell);
+
+   nsCOMPtr<nsIScrollable> scroll(do_QueryInterface(mDocShell));
+
+   NS_ENSURE_TRUE(scroll, NS_ERROR_FAILURE);
+
+   return scroll->ResetScrollbarPreferences();
 }
 
 NS_IMETHODIMP nsWebBrowser::GetScrollbarVisibility(PRBool* verticalVisible,
diff --git a/mozilla/layout/generic/nsFrameFrame.cpp b/mozilla/layout/generic/nsFrameFrame.cpp
index df8d0c67add..55b68aba99b 100644
--- a/mozilla/layout/generic/nsFrameFrame.cpp
+++ b/mozilla/layout/generic/nsFrameFrame.cpp
@@ -58,6 +58,7 @@
 #include "nsLayoutAtoms.h"
 #include "nsIChromeEventHandler.h"
 #include "nsIScriptSecurityManager.h"
+#include "nsIScrollable.h"
 
 class nsHTMLFrame;
 
@@ -704,7 +705,12 @@ nsHTMLFrameInnerFrame::CreateWebShell(nsIPresContext* aPresContext,
   // Current and initial scrolling is set so that all succeeding docs
   // will use the scrolling value set here, regardless if scrolling is
   // set by viewing a particular document (e.g. XUL turns off scrolling)
-  mWebShell->SetScrolling(GetScrolling(content, mode));
+  nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(mWebShell, &rv);
+  if (NS_SUCCEEDED(rv) && scrollableContainer) {
+    scrollableContainer->SetDefaultScrollbarPreferences(nsIScrollable::ScrollOrientation_Y, GetScrolling(content, mode));
+    scrollableContainer->SetDefaultScrollbarPreferences(nsIScrollable::ScrollOrientation_X, GetScrolling(content, mode));
+  }
+
   nsString frameName;
   if (GetName(content, frameName)) {
     docShellAsItem->SetName(frameName.GetUnicode());
diff --git a/mozilla/layout/html/base/src/nsScrollFrame.cpp b/mozilla/layout/html/base/src/nsScrollFrame.cpp
index ea1b0cc11e4..16f53b22bb1 100644
--- a/mozilla/layout/html/base/src/nsScrollFrame.cpp
+++ b/mozilla/layout/html/base/src/nsScrollFrame.cpp
@@ -40,6 +40,7 @@
 #include "nsIWebShell.h"
 #include "nsIBox.h"
 #include "nsIScrollableFrame.h"
+#include "nsIScrollable.h"
 
 #undef NOISY_SECOND_REFLOW
 
@@ -360,19 +361,21 @@ nsScrollFrame::CreateScrollingView(nsIPresContext* aPresContext)
     // has its scrolling set, use that value
     // XXX This is a huge hack, and we should not be checking the web shell's
     // scrolling preference...
+    // This is needed to preserve iframe/frameset scrolling prefs between doc loads.
     nsIFrame* parentFrame = nsnull;
     GetParent(&parentFrame);
-    nsIAtom* frameType = nsnull;
-    parent->GetFrameType(&frameType);
-    if (nsLayoutAtoms::viewportFrame == frameType) {
+    nsCOMPtr<nsIAtom> frameType;
+    parent->GetFrameType(getter_AddRefs(frameType));
+    if (nsLayoutAtoms::viewportFrame == frameType.get()) {
       nsCOMPtr<nsISupports> container;
       rv = aPresContext->GetContainer(getter_AddRefs(container));
       if (NS_SUCCEEDED(rv) && container) {
-        nsCOMPtr<nsIWebShell> webShell;
-        rv = container->QueryInterface(kIWebShellIID, getter_AddRefs(webShell));
-        if (NS_SUCCEEDED(rv)) {
+        nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(container, &rv);
+        if (NS_SUCCEEDED(rv) && scrollableContainer) {
           PRInt32 scrolling = -1; // -1 indicates not set
-          webShell->GetScrolling(scrolling);
+
+          // XXX We should get prefs for X and Y and deal with these independently!
+          scrollableContainer->GetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y,&scrolling);
           if (-1 != scrolling) {
             if (NS_STYLE_OVERFLOW_SCROLL == scrolling) {
               scrollPref = nsScrollPreference_kAlwaysScroll;
@@ -383,7 +386,6 @@ nsScrollFrame::CreateScrollingView(nsIPresContext* aPresContext)
         }
       }
     }
-    NS_IF_RELEASE(frameType);
     scrollingView->SetScrollPreference(scrollPref);
 
     // Set the scrolling view's insets to whatever our border is
diff --git a/mozilla/layout/html/document/src/nsFrameFrame.cpp b/mozilla/layout/html/document/src/nsFrameFrame.cpp
index df8d0c67add..55b68aba99b 100644
--- a/mozilla/layout/html/document/src/nsFrameFrame.cpp
+++ b/mozilla/layout/html/document/src/nsFrameFrame.cpp
@@ -58,6 +58,7 @@
 #include "nsLayoutAtoms.h"
 #include "nsIChromeEventHandler.h"
 #include "nsIScriptSecurityManager.h"
+#include "nsIScrollable.h"
 
 class nsHTMLFrame;
 
@@ -704,7 +705,12 @@ nsHTMLFrameInnerFrame::CreateWebShell(nsIPresContext* aPresContext,
   // Current and initial scrolling is set so that all succeeding docs
   // will use the scrolling value set here, regardless if scrolling is
   // set by viewing a particular document (e.g. XUL turns off scrolling)
-  mWebShell->SetScrolling(GetScrolling(content, mode));
+  nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(mWebShell, &rv);
+  if (NS_SUCCEEDED(rv) && scrollableContainer) {
+    scrollableContainer->SetDefaultScrollbarPreferences(nsIScrollable::ScrollOrientation_Y, GetScrolling(content, mode));
+    scrollableContainer->SetDefaultScrollbarPreferences(nsIScrollable::ScrollOrientation_X, GetScrolling(content, mode));
+  }
+
   nsString frameName;
   if (GetName(content, frameName)) {
     docShellAsItem->SetName(frameName.GetUnicode());
diff --git a/mozilla/layout/html/document/src/nsHTMLContentSink.cpp b/mozilla/layout/html/document/src/nsHTMLContentSink.cpp
index a4a0c931c87..a95df350160 100644
--- a/mozilla/layout/html/document/src/nsHTMLContentSink.cpp
+++ b/mozilla/layout/html/document/src/nsHTMLContentSink.cpp
@@ -93,6 +93,7 @@
 #include "nsITimer.h"
 #include "nsITimerCallback.h"
 #include "nsDOMError.h"
+#include "nsIScrollable.h"
 
 #ifdef ALLOW_ASYNCH_STYLE_SHEETS
 const PRBool kBlock=PR_FALSE;
@@ -3023,11 +3024,19 @@ HTMLContentSink::StartLayout()
   mLastNotificationTime = PR_Now();
 
   // If it's a frameset document then disable scrolling.
-  // Scrolling was reset nsWebShell::LoadURL() by InitFrameData()
+  // Else, reset scrolling to default settings for this shell.
+  // This must happen before the initial reflow, when we create the root frame
+  nsresult rv;
   if (mWebShell) {
-    if (mFrameset) {
-      mWebShell->SetScrolling(NS_STYLE_OVERFLOW_HIDDEN, PR_FALSE);
-    } 
+    nsCOMPtr<nsIScrollable> scrollableContainer = do_QueryInterface(mWebShell, &rv);
+    if (NS_SUCCEEDED(rv) && scrollableContainer) {
+      if (mFrameset) {
+        scrollableContainer->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_Y, NS_STYLE_OVERFLOW_HIDDEN);
+        scrollableContainer->SetCurrentScrollbarPreferences(nsIScrollable::ScrollOrientation_X, NS_STYLE_OVERFLOW_HIDDEN);
+      } else {
+        scrollableContainer->ResetScrollbarPreferences();
+      }
+    }
   }
 
   PRInt32 i, ns = mDocument->GetNumberOfShells();
@@ -3057,7 +3066,7 @@ HTMLContentSink::StartLayout()
   // frameset document, disable the scroll bars on the views.
   char* ref = nsnull;           // init in case mDocumentURI is not a url
   nsIURL* url;
-  nsresult rv = mDocumentURI->QueryInterface(NS_GET_IID(nsIURL), (void**)&url);
+  rv = mDocumentURI->QueryInterface(NS_GET_IID(nsIURL), (void**)&url);
   if (NS_SUCCEEDED(rv)) {
     rv = url->GetRef(&ref);
     NS_RELEASE(url);
diff --git a/mozilla/webshell/public/nsIWebShell.h b/mozilla/webshell/public/nsIWebShell.h
index 4c9f672366a..0e98ebd6542 100644
--- a/mozilla/webshell/public/nsIWebShell.h
+++ b/mozilla/webshell/public/nsIWebShell.h
@@ -120,7 +120,6 @@ public:
    */
   NS_IMETHOD Init(nsNativeWidget aNativeParent,
                   PRInt32 x, PRInt32 y, PRInt32 w, PRInt32 h,
-                  nsScrollPreference aScrolling = nsScrollPreference_kAuto,
                   PRBool aAllowPlugins = PR_TRUE,
                   PRBool aIsSunkenBorder = PR_FALSE) = 0;
 
@@ -316,11 +315,6 @@ public:
   // SetMenuBar
   // SetStatusBar
 
-  NS_IMETHOD SetScrolling(PRInt32 aScrolling, PRBool aSetCurrentAndInitial = PR_TRUE)  = 0;
-  NS_IMETHOD GetScrolling(PRInt32& aScrolling) = 0;
-
-
-
   // XXX these are here until there a better way to pass along info to a sub doc
   NS_IMETHOD GetMarginWidth (PRInt32* aWidth)  = 0;
   NS_IMETHOD SetMarginWidth (PRInt32  aWidth)  = 0;
diff --git a/mozilla/webshell/src/nsWebShell.cpp b/mozilla/webshell/src/nsWebShell.cpp
index 705a3234379..1a054087ae1 100644
--- a/mozilla/webshell/src/nsWebShell.cpp
+++ b/mozilla/webshell/src/nsWebShell.cpp
@@ -215,7 +215,6 @@ public:
   // nsIWebShell
   NS_IMETHOD Init(nsNativeWidget aNativeParent,
                   PRInt32 x, PRInt32 y, PRInt32 w, PRInt32 h,
-                  nsScrollPreference aScrolling = nsScrollPreference_kAuto,
                   PRBool aAllowPlugins = PR_TRUE,
                   PRBool aIsSunkenBorder = PR_FALSE);
   NS_IMETHOD SetContainer(nsIWebShellContainer* aContainer);
@@ -235,9 +234,6 @@ public:
   NS_IMETHOD FindChildWithName(const PRUnichar* aName,
                                nsIWebShell*& aResult);
 
-  NS_IMETHOD GetScrolling(PRInt32& aScrolling);
-  NS_IMETHOD SetScrolling(PRInt32 aScrolling, PRBool aSetCurrentAndInitial = PR_TRUE);
-
   // Document load api's
   NS_IMETHOD GetDocumentLoader(nsIDocumentLoader*& aResult);
   NS_IMETHOD LoadURL(const PRUnichar *aURLSpec,
@@ -375,7 +371,7 @@ public:
 
 protected:
   void GetRootWebShellEvenIfChrome(nsIWebShell** aResult);
-  void InitFrameData(PRBool aCompleteInitScrolling);
+  void InitFrameData();
   nsresult CheckForTrailingSlash(nsIURI* aURL);
   nsresult GetViewManager(nsIViewManager* *viewManager);
   nsresult InitDialogVars(void);
@@ -412,7 +408,6 @@ protected:
 
   nsScrollPreference mScrollPref;
 
-  PRInt32 mScrolling[2];
   nsVoidArray mRefreshments;
 
   eCharsetReloadState mCharsetReloadState;
@@ -585,7 +580,7 @@ nsWebShell::nsWebShell() : nsDocShell()
   mHistoryIndex = -1;
   mScrollPref = nsScrollPreference_kAuto;
   mThreadEventQueue = nsnull;
-  InitFrameData(PR_TRUE);
+  InitFrameData();
   mItemType = typeContent;
   mSHist = nsnull;
   mIsInSHist = PR_FALSE;
@@ -636,7 +631,7 @@ nsWebShell::~nsWebShell()
     mScriptContext = nsnull;
   }
 
-  InitFrameData(PR_TRUE);
+  InitFrameData();
 
   // Free up history memory
   PRInt32 i, n = mHistory.Count();
@@ -657,17 +652,10 @@ nsWebShell::~nsWebShell()
 #endif
 }
 
-void nsWebShell::InitFrameData(PRBool aCompleteInitScrolling)
+void nsWebShell::InitFrameData()
 {
-  if (aCompleteInitScrolling) {
-    mScrolling[0] = -1;
-    mScrolling[1] = -1;
-    SetMarginWidth(-1);    
-    SetMarginHeight(-1);
-  }
-  else {
-    mScrolling[1] = mScrolling[0];
-  }
+  SetMarginWidth(-1);    
+  SetMarginHeight(-1);
 }
 
 nsresult
@@ -754,6 +742,7 @@ NS_INTERFACE_MAP_BEGIN(nsWebShell)
    NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeItem)
    NS_INTERFACE_MAP_ENTRY(nsIDocShellTreeNode)
    NS_INTERFACE_MAP_ENTRY(nsIWebNavigation)
+   NS_INTERFACE_MAP_ENTRY(nsIScrollable)
 NS_INTERFACE_MAP_END
 
 NS_IMETHODIMP
@@ -959,7 +948,6 @@ nsWebShell::HandleUnknownContentType(nsIDocumentLoader* loader,
 NS_IMETHODIMP
 nsWebShell::Init(nsNativeWidget aNativeParent,
                  PRInt32 x, PRInt32 y, PRInt32 w, PRInt32 h,
-                 nsScrollPreference aScrolling,
                  PRBool aAllowPlugins,
                  PRBool aIsSunkenBorder)
 {
@@ -990,8 +978,6 @@ nsWebShell::Init(nsNativeWidget aNativeParent,
 
   CreatePluginHost(aAllowPlugins);
 
-  //mScrollPref = aScrolling;
-
   WEB_TRACE(WEB_TRACE_CALLS,
             ("nsWebShell::Init: this=%p", this));
 
@@ -1306,24 +1292,6 @@ nsWebShell::FindChildWithName(const PRUnichar* aName1,
    return NS_OK;
 }
 
-NS_IMETHODIMP
-nsWebShell::GetScrolling(PRInt32& aScrolling)
-{
-  aScrolling = mScrolling[1];
-  return NS_OK;
-}
-
-NS_IMETHODIMP
-nsWebShell::SetScrolling(PRInt32 aScrolling, PRBool aSetCurrentAndInitial)
-{
-  mScrolling[1] = aScrolling;
-  if (aSetCurrentAndInitial) {
-    mScrolling[0] = aScrolling;
-  }
-  return NS_OK;
-}
-
-
 /**
  * Document Load methods
  */
@@ -1389,11 +1357,6 @@ nsWebShell::LoadURL(const PRUnichar *aURLSpec,
                     nsISupports * aHistoryState,
                     const PRUnichar* aReferrer)
 {
-  // Initialize margnwidth, marginheight. Put scrolling back the way it was
-  // before the last document was loaded.
-
-  InitFrameData(PR_FALSE);
-
   const char *cmd = mViewSource ? "view-source" : "view" ;
 
   return LoadURL(aURLSpec, cmd, aPostDataStream,
@@ -3843,7 +3806,6 @@ NS_IMETHODIMP nsWebShell::SetDocument(nsIDOMDocument *aDOMDoc,
   rootContent->SetDocument(doc, PR_TRUE);
 
   // (6) reflow the document
-  InitFrameData(PR_FALSE);  // Reset the scrolling state to initial
   PRInt32 i;
   PRInt32 ns = doc->GetNumberOfShells();
   for (i = 0; i < ns; i++)