--- a/mail/app/profile/all-thunderbird.js
+++ b/mail/app/profile/all-thunderbird.js
@@ -653,8 +653,23 @@ pref("places.frecency.permRedirectVisitB
 pref("places.frecency.tempRedirectVisitBonus", 0);
 pref("places.frecency.defaultVisitBonus", 0);
 
 // bonus (in percent) for place types for frecency calculations
 pref("places.frecency.unvisitedBookmarkBonus", 140);
 pref("places.frecency.unvisitedTypedBonus", 200);
 
 pref("browser.urlbar.restrict.openpage", "%");
+
+// The default for this pref reflects whether the build is capable of IPC.
+// (Turning it on in a no-IPC build will have no effect.)
+#ifdef XP_MACOSX
+// i386 ipc preferences
+pref("dom.ipc.plugins.enabled.i386", false);
+pref("dom.ipc.plugins.enabled.i386.flash player.plugin", true);
+pref("dom.ipc.plugins.enabled.i386.javaplugin2_npapi.plugin", true);
+// x86_64 ipc preferences
+pref("dom.ipc.plugins.enabled.x86_64", true);
+#elifdef MOZ_IPC
+pref("dom.ipc.plugins.enabled", true);
+#else
+pref("dom.ipc.plugins.enabled", false);
+#endif

--- a/mail/installer/Makefile.in
+++ b/mail/installer/Makefile.in
@@ -75,16 +75,21 @@ DEFINES += -DJAREXT=.jar
 else
 DEFINES += -DJAREXT=
 endif
 
 ifdef MOZ_UPDATER
 DEFINES += -DMOZ_UPDATER=1
 endif
 
+ifdef MOZ_IPC
+include $(MOZILLA_SRCDIR)/ipc/app/defs.mk
+DEFINES += -DMOZ_CHILD_PROCESS_NAME=$(MOZ_CHILD_PROCESS_NAME)
+endif
+
 ifdef MOZ_PKG_MANIFEST_P
 MOZ_PKG_MANIFEST = package-manifest
 
 $(MOZ_PKG_MANIFEST): $(MOZ_PKG_MANIFEST_P)
 	$(PYTHON) $(MOZILLA_SRCDIR)/config/Preprocessor.py $(DEFINES) $(ACDEFINES) $< > $@
 endif
 
 ifeq (cocoa,$(MOZ_WIDGET_TOOLKIT))

--- a/mail/installer/package-manifest.in
+++ b/mail/installer/package-manifest.in
@@ -35,19 +35,16 @@
 @BINPATH@/update.locale
 @BINPATH@/updater.ini
 
 [xpcom]
 @BINPATH@/@DLL_PREFIX@xpcom@DLL_SUFFIX@
 @BINPATH@/@DLL_PREFIX@nspr4@DLL_SUFFIX@
 @BINPATH@/@DLL_PREFIX@plc4@DLL_SUFFIX@
 @BINPATH@/@DLL_PREFIX@plds4@DLL_SUFFIX@
-#ifdef MOZ_IPC
-@BINPATH@/mozilla-runtime@BIN_SUFFIX@
-#endif
 #ifndef MOZ_STATIC_JS
 @BINPATH@/@DLL_PREFIX@mozjs@DLL_SUFFIX@
 #endif
 #ifdef XP_WIN32
 #ifndef MOZ_MEMORY
 #if _MSC_VER == 1400
 @BINPATH@/Microsoft.VC80.CRT.manifest
 @BINPATH@/msvcm80.dll
@@ -68,16 +65,23 @@
 #endif
 #endif
 @BINPATH@/@DLL_PREFIX@mozalloc@DLL_SUFFIX@
 #ifdef XP_MACOSX
 @BINPATH@/XUL
 #else
 @BINPATH@/@DLL_PREFIX@xul@DLL_SUFFIX@
 #endif
+#ifdef MOZ_IPC
+#ifdef XP_MACOSX
+@BINPATH@/@MOZ_CHILD_PROCESS_NAME@.app/
+#else
+@BINPATH@/@MOZ_CHILD_PROCESS_NAME@
+#endif
+#endif
 
 ; Modules
 @BINPATH@/modules/*
 
 ; Optional RSS extension
 [newsblog]
 @BINPATH@/chrome/newsblog@JAREXT@
 @BINPATH@/chrome/newsblog.manifest
@@ -126,31 +130,38 @@
 @BINPATH@/components/aboutRedirector.js
 @BINPATH@/components/activity.xpt
 @BINPATH@/components/activityComponents.manifest
 @BINPATH@/components/addrbook.xpt
 @BINPATH@/components/fts3tok.xpt
 ; interfaces.manifest doesn't get packaged because it is dynamically
 ; re-created at packaging time when linking the xpts that will actually
 ; go into the package, so the test related interfaces aren't included.
+#ifdef MOZ_IPC
+@BINPATH@/components/jetpack.xpt
+#endif
 @BINPATH@/components/mime.xpt
 @BINPATH@/components/steel.xpt
 @BINPATH@/components/msgAsyncPrompter.js
 @BINPATH@/components/msgbase.xpt
 @BINPATH@/components/msgBase.manifest
 @BINPATH@/components/msgcompose.xpt
 @BINPATH@/components/msgdb.xpt
 @BINPATH@/components/msgimap.xpt
 @BINPATH@/components/msglocal.xpt
 @BINPATH@/components/msgnews.xpt
 @BINPATH@/components/msgsearch.xpt
 @BINPATH@/components/import.xpt
 @BINPATH@/components/impComm4xMail.xpt
 @BINPATH@/components/mailview.xpt
 @BINPATH@/components/mailprofilemigration.xpt
+#ifdef MOZ_IPC
+@BINPATH@/components/messageWakeupService.js
+@BINPATH@/components/messageWakeupService.manifest
+#endif
 @BINPATH@/components/nsActivity.js
 @BINPATH@/components/nsActivityManager.js
 @BINPATH@/components/nsActivityManagerUI.js
 @BINPATH@/components/nsAddrbook.manifest
 @BINPATH@/components/nsMailNewsCommandLineHandler.js
 @BINPATH@/components/services-crypto-component.xpt
 #ifndef XP_OS2
 @BINPATH@/components/shellservice.xpt

--- a/mail/installer/removed-files.in
+++ b/mail/installer/removed-files.in
@@ -211,19 +211,17 @@ isp/sv-SE/gmail.rdf
 isp/tr/gmail.rdf
 isp/uk/gmail.rdf
 isp/zh-CN/gmail.rdf
 isp/zh-TW/gmail.rdf
 license.html
 LICENSE.txt
 modules/JSON.jsm
 modules/quickSearchManager.js
-#ifndef MOZ_IPC
-  mozilla-runtime@BIN_SUFFIX@
-#endif
+mozilla-runtime@BIN_SUFFIX@
 #ifdef XP_MACOSX
   ../Plug-Ins/PrintPDE.plugin/Contents/Info.plist
   ../Plug-Ins/PrintPDE.plugin/Contents/MacOS/PrintPDE
   ../Plug-Ins/PrintPDE.plugin/Contents/Resources/English.lproj/Localizable.strings
   ../Plug-Ins/PrintPDE.plugin/Contents/Resources/English.lproj/PrintPDE.nib/classes.nib
   ../Plug-Ins/PrintPDE.plugin/Contents/Resources/English.lproj/PrintPDE.nib/info.nib
   ../Plug-Ins/PrintPDE.plugin/Contents/Resources/English.lproj/PrintPDE.nib/objects.xib
 #endif