diff --git a/uriloader/exthandler/nsIExternalProtocolService.idl b/uriloader/exthandler/nsIExternalProtocolService.idl
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+/* -*- Mode: C++; tab-width: 3; indent-tabs-mode: nil; c-basic-offset: 2 -*-
+ *
+ * The contents of this file are subject to the Mozilla 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/MPL/
+ * 
+ * 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 the Mozilla browser.
+ * 
+ * The Initial Developer of the Original Code is Netscape
+ * Communications, Inc.  Portions created by Netscape are
+ * Copyright (C) 1999, Mozilla.  All Rights Reserved.
+ * 
+ * Contributor(s):
+ *   Scott MacGregor <mscott@netscape.com>
+ */
+
+/* The external protocol service is used for finding and launching
+   platform specific applications for particular protocols.
+
+   You can ask the external protocol service if it has an external
+   handler for a given protocol scheme. And you can ask it to load 
+   the url using the default handler...
+ */
+
+#include "nsISupports.idl"
+
+interface nsIURI;
+
+[scriptable, uuid(100FD4B3-4557-11d4-98D0-001083010E9B)]
+interface nsIExternalProtocolService : nsISupports
+{
+  // aProtocolScheme --> the scheme from a url: http, ftp, mailto, etc.
+  // returns true if we have a handler and false otherwise...
+  boolean externalProtocolHandlerExists(in string aProtocolScheme);
+
+  // used to load a url via an external protocol handler (if one exists)
+  // aURL --> the url to load
+  void loadUrl (in nsIURI aURL);  
+};