diff --git a/mozilla/mailnews/base/build/nsMsgBaseCID.h b/mozilla/mailnews/base/build/nsMsgBaseCID.h
index 6411c8937a4..4df74f7522c 100644
--- a/mozilla/mailnews/base/build/nsMsgBaseCID.h
+++ b/mozilla/mailnews/base/build/nsMsgBaseCID.h
@@ -180,6 +180,14 @@
 { 0xc766e666, 0x29bd, 0x11d3, \
     { 0xaf, 0xb3, 0x00, 0x10, 0x83, 0x00, 0x2d, 0xa8 } }
 
+#define NS_MSGFOLDERCACHE_PROGID \
+	"component://netscape/messenger/msgFolderCache"
+
+/* bcdca970-3b22-11d3-8d76-00805f8a6617 */
+#define NS_MSGFOLDERCACHE_CID \
+{ 0xbcdca970, 0x3b22, 0x11d3,  \
+	{ 0x8d, 0x76, 0x00, 0x80, 0xf5, 0x8a, 0x66, 0x17 } }
+
 //
 // nsUrlListenerManager
 //
diff --git a/mozilla/mailnews/base/build/nsMsgFactory.cpp b/mozilla/mailnews/base/build/nsMsgFactory.cpp
index 3e9212767c5..9fa1a444eda 100644
--- a/mozilla/mailnews/base/build/nsMsgFactory.cpp
+++ b/mozilla/mailnews/base/build/nsMsgFactory.cpp
@@ -102,6 +102,8 @@ static NS_DEFINE_CID(kCopyMessageStreamListenerCID,
                      NS_COPYMESSAGESTREAMLISTENER_CID);
 static NS_DEFINE_CID(kMsgCopyServiceCID, NS_MSGCOPYSERVICE_CID);
 
+// Msg Folder Cache stuff
+static NS_DEFINE_CID(kMsgFolderCacheCID, NS_MSGFOLDERCACHE_CID);
 ////////////////////////////////////////////////////////////
 //
 ////////////////////////////////////////////////////////////
@@ -284,6 +286,9 @@ nsMsgFactory::CreateInstance(nsISupports * /* aOuter */,
   else if (mClassID.Equals(kMsgCopyServiceCID)) {
       rv = NS_NewMsgCopyService(aIID, aResult);
   }
+  else if (mClassID.Equals(kMsgFolderCacheCID)) {
+		rv = NS_ERROR_NO_INTERFACE;
+  }
 
   return rv;
 }  
@@ -489,6 +494,12 @@ NSRegisterSelf(nsISupports* aServMgr, const char* path)
                                   path, PR_TRUE, PR_TRUE);
   if (NS_FAILED(rv)) finalResult = rv;
 
+	rv = compMgr->RegisterComponent(kMsgFolderCacheCID,
+                                  "Mail/News Folder Cache",
+                                  NS_MSGFOLDERCACHE_PROGID,
+                                  path, PR_TRUE, PR_TRUE);
+  if (NS_FAILED(rv)) finalResult = rv;
+
   return finalResult;
 }