--- a/browser/confvars.sh
+++ b/browser/confvars.sh
@@ -36,16 +36,22 @@
 #
 # ***** END LICENSE BLOCK *****
 
 MOZ_APP_BASENAME=Firefox
 MOZ_APP_VENDOR=Mozilla
 MOZ_UPDATER=1
 MOZ_PHOENIX=1
 
+if test "$OS_ARCH" = "WINNT"; then
+  if ! test "$HAVE_64BIT_OS"; then
+    MOZ_MAINTENANCE_SERVICE=1
+  fi
+fi
+
 MOZ_CHROME_FILE_FORMAT=omni
 MOZ_SAFE_BROWSING=1
 MOZ_SERVICES_SYNC=1
 MOZ_APP_VERSION=$FIREFOX_VERSION
 MOZ_EXTENSIONS_DEFAULT=" gnomevfs"
 # MOZ_APP_DISPLAYNAME will be set by branding/configure.sh
 # Changing either of these values requires a clobber to ensure correct results,
 # because branding dependencies are broken.

--- a/config/autoconf.mk.in
+++ b/config/autoconf.mk.in
@@ -131,16 +131,17 @@ INCREMENTAL_LINKER = @INCREMENTAL_LINKER
 MACOSX_DEPLOYMENT_TARGET = @MACOSX_DEPLOYMENT_TARGET@
 ENABLE_TESTS	= @ENABLE_TESTS@
 IBMBIDI = @IBMBIDI@
 MOZ_UNIVERSALCHARDET = @MOZ_UNIVERSALCHARDET@
 ACCESSIBILITY = @ACCESSIBILITY@
 MOZ_BRANDING_DIRECTORY = @MOZ_BRANDING_DIRECTORY@
 XPCOM_USE_LEA = @XPCOM_USE_LEA@
 MOZ_INSTALLER	= @MOZ_INSTALLER@
+MOZ_MAINTENANCE_SERVICE	= @MOZ_MAINTENANCE_SERVICE@
 MOZ_UPDATER	= @MOZ_UPDATER@
 MOZ_UPDATE_CHANNEL	= @MOZ_UPDATE_CHANNEL@
 MOZ_UPDATE_PACKAGING	= @MOZ_UPDATE_PACKAGING@
 MOZ_DISABLE_PARENTAL_CONTROLS = @MOZ_DISABLE_PARENTAL_CONTROLS@
 NS_ENABLE_TSF = @NS_ENABLE_TSF@
 MOZ_SPELLCHECK = @MOZ_SPELLCHECK@
 MOZ_ANDROID_HISTORY = @MOZ_ANDROID_HISTORY@
 MOZ_JAVA_COMPOSITOR = @MOZ_JAVA_COMPOSITOR@

--- a/configure.in
+++ b/configure.in
@@ -6329,16 +6329,33 @@ AC_MSG_RESULT([$TAR])
 AC_SUBST(TAR)
 
 AC_MSG_CHECKING([for wget])
 AC_CHECK_PROGS(WGET, wget, "")
 AC_MSG_RESULT([$WGET])
 AC_SUBST(WGET)
 
 dnl ========================================================
+dnl Maintenance Service
+dnl ========================================================
+
+MOZ_ARG_ENABLE_BOOL(maintenance-service,
+[  --enable-maintenance-service       Enable building of maintenanceservice],
+    MOZ_MAINTENANCE_SERVICE=1,
+    MOZ_MAINTENANCE_SERVICE= )
+
+if test -n "$MOZ_MAINTENANCE_SERVICE"; then
+  if test "$OS_ARCH" = "WINNT"; then
+    AC_DEFINE(MOZ_MAINTENANCE_SERVICE)
+  else
+    AC_MSG_ERROR([Can only build with --enable-maintenance-service with a Windows target])
+  fi
+fi
+
+dnl ========================================================
 dnl Updater
 dnl ========================================================
 
 MOZ_ARG_DISABLE_BOOL(updater,
 [  --disable-updater       Disable building of updater],
     MOZ_UPDATER=,
     MOZ_UPDATER=1 )
 
@@ -8419,16 +8436,17 @@ AC_SUBST(MOZ_PROFILELOCKING)
 AC_SUBST(ENABLE_TESTS)
 AC_SUBST(IBMBIDI)
 AC_SUBST(MOZ_UNIVERSALCHARDET)
 AC_SUBST(ACCESSIBILITY)
 AC_SUBST(MOZ_SPELLCHECK)
 AC_SUBST(MOZ_JAVA_COMPOSITOR)
 AC_SUBST(MOZ_USER_DIR)
 AC_SUBST(MOZ_CRASHREPORTER)
+AC_SUBST(MOZ_MAINTENANCE_SERVICE)
 AC_SUBST(MOZ_UPDATER)
 AC_SUBST(MOZ_ANGLE)
 AC_SUBST(MOZ_DIRECTX_SDK_PATH)
 AC_SUBST(MOZ_DIRECTX_SDK_CPU_SUFFIX)
 AC_SUBST(MOZ_D3DX9_VERSION)
 AC_SUBST(MOZ_D3DX9_CAB)
 AC_SUBST(MOZ_D3DCOMPILER_CAB)
 AC_SUBST(MOZ_D3DX9_DLL)