diff --git a/editor/base/nsEditorParserObserver.cpp b/editor/base/nsEditorParserObserver.cpp
new file mode 100644
index 000000000000..7c2061508d63
--- /dev/null
+++ b/editor/base/nsEditorParserObserver.cpp
@@ -0,0 +1,124 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ *   steve clark <buster@netscape.com>
+ */
+
+#include "nsIServiceManager.h"
+
+#include "nsEditorParserObserver.h"
+
+
+NS_IMPL_ADDREF(nsEditorParserObserver);
+NS_IMPL_RELEASE(nsEditorParserObserver);
+
+NS_INTERFACE_MAP_BEGIN(nsEditorParserObserver)
+      NS_INTERFACE_MAP_ENTRY(nsIElementObserver)
+      NS_INTERFACE_MAP_ENTRY(nsIObserver)
+      NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+      NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIElementObserver)
+NS_INTERFACE_MAP_END
+
+nsEditorParserObserver::nsEditorParserObserver()
+: mBadTagFound(PR_FALSE)
+{
+  NS_INIT_REFCNT();
+}
+
+nsEditorParserObserver::~nsEditorParserObserver()
+{
+}
+
+NS_IMETHODIMP_(const char*) nsEditorParserObserver::GetTagNameAt(PRUint32 aTagIndex)
+{
+  if (aTagIndex < gParserObserver_TagCount)
+  {
+    return gParserObserver_Tags[aTagIndex];
+  } else {
+    return nsnull;
+  }
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Notify(
+                     PRUint32 aDocumentID, 
+                     const PRUnichar* aTag, 
+                     PRUint32 numOfAttributes, 
+                     const PRUnichar* nameArray[], 
+                     const PRUnichar* valueArray[])
+{
+  // XXX based on aTag...
+  Notify();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Notify(
+                     PRUint32 aDocumentID, 
+                     eHTMLTags aTag, 
+                     PRUint32 numOfAttributes, 
+                     const PRUnichar* nameArray[], 
+                     const PRUnichar* valueArray[])
+{
+  if (eHTMLTag_frameset == aTag)
+  {
+    Notify();
+    return NS_OK;
+  }
+  else
+    return NS_ERROR_ILLEGAL_VALUE;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Observe(nsISupports*, const PRUnichar*, const PRUnichar*)
+{
+    return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+void nsEditorParserObserver::Notify()
+{
+  mBadTagFound = PR_TRUE;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Start() 
+{
+  nsresult res = NS_OK;
+  nsAutoString parserService("text/html");
+
+  nsCOMPtr<nsIObserverService> anObserverService = do_GetService(NS_OBSERVERSERVICE_PROGID, &res);
+  if (NS_FAILED(res)) return res;
+   
+  return anObserverService->AddObserver(this, parserService.GetUnicode());
+}
+
+NS_IMETHODIMP nsEditorParserObserver::End() 
+{
+  nsresult res = NS_OK;
+  nsAutoString parserService("text/html");
+
+  nsCOMPtr<nsIObserverService> anObserverService = do_GetService(NS_OBSERVERSERVICE_PROGID, &res);
+  if (NS_FAILED(res)) return res;
+   
+  return anObserverService->RemoveObserver(this, parserService.GetUnicode());
+}
+
+NS_IMETHODIMP nsEditorParserObserver::GetBadTagFound(PRBool *aFound)
+{
+  NS_ENSURE_ARG_POINTER(aFound);
+  *aFound = mBadTagFound;
+  return NS_OK; 
+}
\ No newline at end of file
diff --git a/editor/base/nsEditorParserObserver.h b/editor/base/nsEditorParserObserver.h
new file mode 100644
index 000000000000..1b03a556b972
--- /dev/null
+++ b/editor/base/nsEditorParserObserver.h
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ *   steve clark <buster@netscape.com>
+ */
+
+#include "nsIElementObserver.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsWeakReference.h"
+
+static const PRInt32 gParserObserver_TagCount=1;
+static const char * gParserObserver_Tags[1] = {"FRAMESET"};
+
+
+// this needs to support the weak reference API, so that the parser
+// does not need to hold a reference
+
+class nsEditorParserObserver : public nsSupportsWeakReference,
+                               public nsIElementObserver,
+                               public nsIObserver
+{
+public:
+
+                            nsEditorParserObserver();
+  virtual                   ~nsEditorParserObserver();
+
+  NS_DECL_ISUPPORTS
+
+  /* method for nsIElementObserver */
+  NS_IMETHOD_(const char*)  GetTagNameAt(PRUint32 aTagIndex);
+  NS_IMETHOD                Notify(PRUint32 aDocumentID, eHTMLTags aTag, PRUint32 numOfAttributes, 
+                                    const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
+  NS_IMETHOD                Notify(PRUint32 aDocumentID, const PRUnichar* aTag, PRUint32 numOfAttributes, 
+                                     const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
+
+  /* methods for nsIObserver */
+  NS_DECL_NSIOBSERVER
+
+  /* begin observing */
+  NS_IMETHOD                Start();
+
+  /** end observing */
+  NS_IMETHOD                End();
+
+  /** query, did we find a bad tag? */
+  NS_IMETHOD                GetBadTagFound(PRBool *aFound);
+
+protected:
+
+  virtual void              Notify();
+  
+  
+protected:
+
+  PRBool                    mBadTagFound;
+  
+};
+
+
diff --git a/editor/composer/src/nsEditorParserObserver.cpp b/editor/composer/src/nsEditorParserObserver.cpp
new file mode 100644
index 000000000000..7c2061508d63
--- /dev/null
+++ b/editor/composer/src/nsEditorParserObserver.cpp
@@ -0,0 +1,124 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ *   steve clark <buster@netscape.com>
+ */
+
+#include "nsIServiceManager.h"
+
+#include "nsEditorParserObserver.h"
+
+
+NS_IMPL_ADDREF(nsEditorParserObserver);
+NS_IMPL_RELEASE(nsEditorParserObserver);
+
+NS_INTERFACE_MAP_BEGIN(nsEditorParserObserver)
+      NS_INTERFACE_MAP_ENTRY(nsIElementObserver)
+      NS_INTERFACE_MAP_ENTRY(nsIObserver)
+      NS_INTERFACE_MAP_ENTRY(nsISupportsWeakReference)
+      NS_INTERFACE_MAP_ENTRY_AMBIGUOUS(nsISupports, nsIElementObserver)
+NS_INTERFACE_MAP_END
+
+nsEditorParserObserver::nsEditorParserObserver()
+: mBadTagFound(PR_FALSE)
+{
+  NS_INIT_REFCNT();
+}
+
+nsEditorParserObserver::~nsEditorParserObserver()
+{
+}
+
+NS_IMETHODIMP_(const char*) nsEditorParserObserver::GetTagNameAt(PRUint32 aTagIndex)
+{
+  if (aTagIndex < gParserObserver_TagCount)
+  {
+    return gParserObserver_Tags[aTagIndex];
+  } else {
+    return nsnull;
+  }
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Notify(
+                     PRUint32 aDocumentID, 
+                     const PRUnichar* aTag, 
+                     PRUint32 numOfAttributes, 
+                     const PRUnichar* nameArray[], 
+                     const PRUnichar* valueArray[])
+{
+  // XXX based on aTag...
+  Notify();
+  return NS_OK;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Notify(
+                     PRUint32 aDocumentID, 
+                     eHTMLTags aTag, 
+                     PRUint32 numOfAttributes, 
+                     const PRUnichar* nameArray[], 
+                     const PRUnichar* valueArray[])
+{
+  if (eHTMLTag_frameset == aTag)
+  {
+    Notify();
+    return NS_OK;
+  }
+  else
+    return NS_ERROR_ILLEGAL_VALUE;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Observe(nsISupports*, const PRUnichar*, const PRUnichar*)
+{
+    return NS_ERROR_NOT_IMPLEMENTED;
+}
+
+void nsEditorParserObserver::Notify()
+{
+  mBadTagFound = PR_TRUE;
+}
+
+NS_IMETHODIMP nsEditorParserObserver::Start() 
+{
+  nsresult res = NS_OK;
+  nsAutoString parserService("text/html");
+
+  nsCOMPtr<nsIObserverService> anObserverService = do_GetService(NS_OBSERVERSERVICE_PROGID, &res);
+  if (NS_FAILED(res)) return res;
+   
+  return anObserverService->AddObserver(this, parserService.GetUnicode());
+}
+
+NS_IMETHODIMP nsEditorParserObserver::End() 
+{
+  nsresult res = NS_OK;
+  nsAutoString parserService("text/html");
+
+  nsCOMPtr<nsIObserverService> anObserverService = do_GetService(NS_OBSERVERSERVICE_PROGID, &res);
+  if (NS_FAILED(res)) return res;
+   
+  return anObserverService->RemoveObserver(this, parserService.GetUnicode());
+}
+
+NS_IMETHODIMP nsEditorParserObserver::GetBadTagFound(PRBool *aFound)
+{
+  NS_ENSURE_ARG_POINTER(aFound);
+  *aFound = mBadTagFound;
+  return NS_OK; 
+}
\ No newline at end of file
diff --git a/editor/composer/src/nsEditorParserObserver.h b/editor/composer/src/nsEditorParserObserver.h
new file mode 100644
index 000000000000..1b03a556b972
--- /dev/null
+++ b/editor/composer/src/nsEditorParserObserver.h
@@ -0,0 +1,77 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Netscape Public
+ * License Version 1.1 (the "License"); you may not use this file
+ * except in compliance with the License. You may obtain a copy of
+ * the License at http://www.mozilla.org/NPL/
+ *
+ * Software distributed under the License is distributed on an "AS
+ * IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
+ * implied. See the License for the specific language governing
+ * rights and limitations under the License.
+ *
+ * The Original Code is mozilla.org code.
+ *
+ * The Initial Developer of the Original Code is Netscape
+ * Communications Corporation.  Portions created by Netscape are
+ * Copyright (C) 1998 Netscape Communications Corporation. All
+ * Rights Reserved.
+ *
+ * Contributor(s): 
+ *   steve clark <buster@netscape.com>
+ */
+
+#include "nsIElementObserver.h"
+#include "nsIObserver.h"
+#include "nsIObserverService.h"
+#include "nsWeakReference.h"
+
+static const PRInt32 gParserObserver_TagCount=1;
+static const char * gParserObserver_Tags[1] = {"FRAMESET"};
+
+
+// this needs to support the weak reference API, so that the parser
+// does not need to hold a reference
+
+class nsEditorParserObserver : public nsSupportsWeakReference,
+                               public nsIElementObserver,
+                               public nsIObserver
+{
+public:
+
+                            nsEditorParserObserver();
+  virtual                   ~nsEditorParserObserver();
+
+  NS_DECL_ISUPPORTS
+
+  /* method for nsIElementObserver */
+  NS_IMETHOD_(const char*)  GetTagNameAt(PRUint32 aTagIndex);
+  NS_IMETHOD                Notify(PRUint32 aDocumentID, eHTMLTags aTag, PRUint32 numOfAttributes, 
+                                    const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
+  NS_IMETHOD                Notify(PRUint32 aDocumentID, const PRUnichar* aTag, PRUint32 numOfAttributes, 
+                                     const PRUnichar* nameArray[], const PRUnichar* valueArray[]);
+
+  /* methods for nsIObserver */
+  NS_DECL_NSIOBSERVER
+
+  /* begin observing */
+  NS_IMETHOD                Start();
+
+  /** end observing */
+  NS_IMETHOD                End();
+
+  /** query, did we find a bad tag? */
+  NS_IMETHOD                GetBadTagFound(PRBool *aFound);
+
+protected:
+
+  virtual void              Notify();
+  
+  
+protected:
+
+  PRBool                    mBadTagFound;
+  
+};
+
+