diff --git a/mozilla/mailnews/extensions/Makefile.in b/mozilla/mailnews/extensions/Makefile.in
index f508a8e2e30..0f825c962a9 100644
--- a/mozilla/mailnews/extensions/Makefile.in
+++ b/mozilla/mailnews/extensions/Makefile.in
@@ -34,5 +34,9 @@ ifdef BUILD_SMIME
 DIRS		= smime
 endif
 
+ifdef BUILD_MAIL_SMOKETEST
+DIRS		= smoketest
+endif
+
 include $(topsrcdir)/config/rules.mk
 
diff --git a/mozilla/mailnews/extensions/makefile.win b/mozilla/mailnews/extensions/makefile.win
index 8af3907601f..d0eb8a1b57b 100644
--- a/mozilla/mailnews/extensions/makefile.win
+++ b/mozilla/mailnews/extensions/makefile.win
@@ -29,4 +29,8 @@ BUILD_SMIME=1
 DIRS=smime
 !endif
 
+!if defined(BUILD_MAIL_SMOKETEST)
+DIRS=smoketest
+!endif
+
 include <$(DEPTH)\config\rules.mak>
diff --git a/mozilla/mailnews/makefiles b/mozilla/mailnews/makefiles
index f8ce6ef086f..c14bf7fc466 100644
--- a/mozilla/mailnews/makefiles
+++ b/mozilla/mailnews/makefiles
@@ -60,3 +60,6 @@ mailnews/extensions/smime/Makefile
 mailnews/extensions/smime/build/Makefile
 mailnews/extensions/smime/src/Makefile
 mailnews/extensions/smime/public/Makefile
+mailnews/extensions/smoketest/Makefile
+mailnews/extensions/smoketest/resources/Makefile
+mailnews/extensions/smoketest/resources/content/Makefile