--- a/ipc/mscom/moz.build
+++ b/ipc/mscom/moz.build
@@ -2,46 +2,56 @@
 # vim: set filetype=python:
 # This Source Code Form is subject to the terms of the Mozilla Public
 # License, v. 2.0. If a copy of the MPL was not distributed with this
 # file, You can obtain one at http://mozilla.org/MPL/2.0/.
 
 EXPORTS.mozilla.mscom += [
     'COMApartmentRegion.h',
     'COMPtrHolder.h',
-    'DispatchForwarder.h',
     'EnsureMTA.h',
-    'Interceptor.h',
-    'InterceptorLog.h',
-    'MainThreadHandoff.h',
-    'MainThreadInvoker.h',
     'MainThreadRuntime.h',
     'ProxyStream.h',
     'Ptr.h',
-    'Registration.h',
     'Utils.h',
-    'WeakRef.h',
 ]
 
 SOURCES += [
-    'Interceptor.cpp',
-    'Registration.cpp',
     'Utils.cpp',
-    'WeakRef.cpp',
 ]
 
 UNIFIED_SOURCES += [
-    'DispatchForwarder.cpp',
     'EnsureMTA.cpp',
-    'InterceptorLog.cpp',
-    'MainThreadHandoff.cpp',
-    'MainThreadInvoker.cpp',
     'MainThreadRuntime.cpp',
     'ProxyStream.cpp',
 ]
 
+if CONFIG['ACCESSIBILITY']:
+    EXPORTS.mozilla.mscom += [
+        'DispatchForwarder.h',
+        'Interceptor.h',
+        'InterceptorLog.h',
+        'MainThreadHandoff.h',
+        'MainThreadInvoker.h',
+        'Registration.h',
+        'WeakRef.h',
+    ]
+
+    SOURCES += [
+        'Interceptor.cpp',
+        'Registration.cpp',
+        'WeakRef.cpp',
+    ]
+
+    UNIFIED_SOURCES += [
+        'DispatchForwarder.cpp',
+        'InterceptorLog.cpp',
+        'MainThreadHandoff.cpp',
+        'MainThreadInvoker.cpp',
+    ]
+
 LOCAL_INCLUDES += [
     '/xpcom/build',
 ]
 
 include('/ipc/chromium/chromium-config.mozbuild')
 
 FINAL_LIBRARY = 'xul'