--- a/docshell/base/nsDocShell.cpp
+++ b/docshell/base/nsDocShell.cpp
@@ -6443,17 +6443,18 @@ nsDocShell::EnsureContentViewer()
         doc->SetIsInitialDocument(PR_TRUE);
     }
 
     return rv;
 }
 
 nsresult
 nsDocShell::CreateAboutBlankContentViewer(nsIPrincipal* aPrincipal,
-                                          nsIURI* aBaseURI)
+                                          nsIURI* aBaseURI,
+                                          PRBool aTryToSaveOldPresentation)
 {
   nsCOMPtr<nsIDocument> blankDoc;
   nsCOMPtr<nsIContentViewer> viewer;
   nsresult rv = NS_ERROR_FAILURE;
 
   /* mCreatingDocument should never be true at this point. However, it's
      a theoretical possibility. We want to know about it and make it stop,
      and this sounds like a job for an assertion. */
@@ -6475,17 +6476,18 @@ nsDocShell::CreateAboutBlankContentViewe
     PRBool okToUnload;
     rv = mContentViewer->PermitUnload(PR_FALSE, &okToUnload);
 
     if (NS_SUCCEEDED(rv) && !okToUnload) {
       // The user chose not to unload the page, interrupt the load.
       return NS_ERROR_FAILURE;
     }
 
-    mSavingOldViewer = CanSavePresentation(LOAD_NORMAL, nsnull, nsnull);
+    mSavingOldViewer = aTryToSaveOldPresentation && 
+                       CanSavePresentation(LOAD_NORMAL, nsnull, nsnull);
 
     // Make sure to blow away our mLoadingURI just in case.  No loads
     // from inside this pagehide.
     mLoadingURI = nsnull;
     
     // Notify the current document that it is about to be unloaded!!
     //
     // It is important to fire the unload() notification *before* any state
@@ -9987,17 +9989,20 @@ nsDocShell::LoadHistoryEntry(nsISHEntry 
     PRBool isJS;
     nsresult rv = uri->SchemeIs("javascript", &isJS);
     if (NS_FAILED(rv) || isJS) {
         // We're loading a URL that will execute script from inside asyncOpen.
         // Replace the current document with about:blank now to prevent
         // anything from the current document from leaking into any JavaScript
         // code in the URL.
         nsCOMPtr<nsIPrincipal> prin = do_QueryInterface(owner);
-        rv = CreateAboutBlankContentViewer(prin, nsnull);
+        // Don't cache the presentation if we're going to just reload the
+        // current entry. Caching would lead to trying to save the different
+        // content viewers in the same nsISHEntry object.
+        rv = CreateAboutBlankContentViewer(prin, nsnull, aEntry != mOSHE);
 
         if (NS_FAILED(rv)) {
             // The creation of the intermittent about:blank content
             // viewer failed for some reason (potentially because the
             // user prevented it). Interrupt the history load.
             return NS_OK;
         }
 

--- a/docshell/base/nsDocShell.h
+++ b/docshell/base/nsDocShell.h
@@ -283,17 +283,18 @@ protected:
     virtual ~nsDocShell();
     virtual void DestroyChildren();
 
     // Content Viewer Management
     NS_IMETHOD EnsureContentViewer();
     // aPrincipal can be passed in if the caller wants.  If null is
     // passed in, the about:blank principal will end up being used.
     nsresult CreateAboutBlankContentViewer(nsIPrincipal* aPrincipal,
-                                           nsIURI* aBaseURI);
+                                           nsIURI* aBaseURI,
+                                           PRBool aTryToSaveOldPresentation = PR_TRUE);
     NS_IMETHOD CreateContentViewer(const char * aContentType, 
         nsIRequest * request, nsIStreamListener ** aContentHandler);
     NS_IMETHOD NewContentViewerObj(const char * aContentType, 
         nsIRequest * request, nsILoadGroup * aLoadGroup, 
         nsIStreamListener ** aContentHandler, nsIContentViewer ** aViewer);
     NS_IMETHOD SetupNewViewer(nsIContentViewer * aNewViewer);
 
     void SetupReferrerFromChannel(nsIChannel * aChannel);