diff --git a/mailnews/base/build/nsMsgBaseCID.h b/mailnews/base/build/nsMsgBaseCID.h
index 90ee25a774c..d7182034270 100644
--- a/mailnews/base/build/nsMsgBaseCID.h
+++ b/mailnews/base/build/nsMsgBaseCID.h
@@ -418,4 +418,20 @@
   {0xd97edfb5, 0xbcbe, 0x4a15, \
     { 0xa4, 0xfb, 0xfb, 0xf2, 0xf9, 0x58, 0xb3, 0x88 }}
 
+#define NS_MSGLOCALFOLDERCOMPACTOR_CONTRACTID \
+  "@mozilla.org/messenger/localfoldercompactor;1"
+
+/* 7d1d315c-e5c6-11d4-a5b7-0060b0fc04b7 */
+#define NS_MSGLOCALFOLDERCOMPACTOR_CID \
+  {0x7d1d315c, 0xe5c6, 0x11d4, \
+    {0xa5, 0xb7, 0x00,0x60, 0xb0, 0xfc, 0x04, 0xb7 }}
+
+#define NS_MSGOFFLINESTORECOMPACTOR_CONTRACTID \
+  "@mozilla.org/messenger/offlinestorecompactor;1"
+
+/* 2db43d16-e5c8-11d4-a5b7-0060b0fc04b7 */
+#define NS_MSG_OFFLINESTORECOMPACTOR_CID \
+  {0x2db43d16, 0xe5c8, 0x11d4, \
+    {0xa5, 0xb7, 0x00,0x60, 0xb0, 0xfc, 0x04, 0xb7 }}
+
 #endif // nsMessageBaseCID_h__
diff --git a/mailnews/base/build/nsMsgFactory.cpp b/mailnews/base/build/nsMsgFactory.cpp
index 307d434f10f..e4a76c45a61 100644
--- a/mailnews/base/build/nsMsgFactory.cpp
+++ b/mailnews/base/build/nsMsgFactory.cpp
@@ -83,7 +83,7 @@
 #include "nsMsgSearchSession.h"
 #include "nsMsgSearchAdapter.h"
 #include "nsMsgSearchDataSource.h"
-
+#include "nsMsgFolderCompactor.h"
 
 // private factory declarations for each component we know how to produce
 
@@ -119,6 +119,8 @@ NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsMsgServiceProviderService, Init);
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsSubscribeDataSource, Init);
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsSubscribableServer, Init);
 NS_GENERIC_FACTORY_CONSTRUCTOR_INIT(nsMsgPrintEngine, Init)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsFolderCompactState)
+NS_GENERIC_FACTORY_CONSTRUCTOR(nsOfflineStoreCompactState)
 
 // The list of components we register
 static nsModuleComponentInfo gComponents[] = {
@@ -283,6 +285,14 @@ static nsModuleComponentInfo gComponents[] = {
 	  NS_SUBSCRIBABLESERVER_CONTRACTID,
 	  nsSubscribableServerConstructor,
     },
+    { "Local folder compactor", NS_MSGLOCALFOLDERCOMPACTOR_CID,
+      NS_MSGLOCALFOLDERCOMPACTOR_CONTRACTID,
+      nsFolderCompactStateConstructor,
+    },
+    { "offline store compactor", NS_MSG_OFFLINESTORECOMPACTOR_CID,
+      NS_MSGOFFLINESTORECOMPACTOR_CONTRACTID,
+      nsOfflineStoreCompactStateConstructor,
+    }
 };
 
 NS_IMPL_NSGETMODULE("nsMsgBaseModule", gComponents)
diff --git a/mailnews/base/util/nsMsgDBFolder.cpp b/mailnews/base/util/nsMsgDBFolder.cpp
index 6e58781df5e..7daa9128412 100644
--- a/mailnews/base/util/nsMsgDBFolder.cpp
+++ b/mailnews/base/util/nsMsgDBFolder.cpp
@@ -35,6 +35,7 @@
 #include "nsLocalFolderSummarySpec.h"
 #include "nsIFileStream.h"
 #include "nsIChannel.h"
+#include "nsIMsgFolderCompactor.h"
 #if defined(XP_OS2)
 #define MAX_FILE_LENGTH_WITHOUT_EXTENSION 8
 #elif defined(XP_MAC)
@@ -1394,3 +1395,22 @@ nsresult nsMsgDBFolder::EndNewOfflineMessage()
   return NS_OK;
 }
 
+nsresult nsMsgDBFolder::CompactOfflineStore(nsIMsgWindow *inWindow)
+{
+  nsresult rv;
+  nsCOMPtr <nsIMsgFolderCompactor> folderCompactor =  do_CreateInstance(NS_MSGOFFLINESTORECOMPACTOR_CONTRACTID, &rv);
+  if (NS_SUCCEEDED(rv) && folderCompactor)
+  {
+    GetDatabase(nsnull);
+    if (NS_SUCCEEDED(rv)) 
+    {
+      nsCOMPtr<nsIFileSpec> pathSpec;
+      rv = GetPath(getter_AddRefs(pathSpec));
+      rv = folderCompactor->Init(this, mBaseMessageURI, mDatabase, pathSpec);
+      if (NS_SUCCEEDED(rv))
+        rv = folderCompactor->StartCompacting();
+    }
+  }
+  return rv;
+}
+
diff --git a/mailnews/base/util/nsMsgDBFolder.h b/mailnews/base/util/nsMsgDBFolder.h
index 02bcebeacc9..049acb0dd11 100644
--- a/mailnews/base/util/nsMsgDBFolder.h
+++ b/mailnews/base/util/nsMsgDBFolder.h
@@ -119,7 +119,7 @@ protected:
   nsresult StartNewOfflineMessage();
   nsresult WriteStartOfNewLocalMessage();
   nsresult EndNewOfflineMessage();
-
+  nsresult CompactOfflineStore(nsIMsgWindow *inWindow);
 
 protected:
 	nsCOMPtr<nsIMsgDatabase> mDatabase;